Method for processing non-real timeservice and broadcast receiver

ABSTRACT

A method of processing a non-real time service of a broadcast receiver, which receives and processes a service being transmitted in non-real time, and a broadcast receiver are disclosed. Herein, the method of processing a non-real time service of a broadcast receiver includes receiving a signaling information table including additional information on contents configuring a non-real time service and a content identifier for each content, acquiring the additional information on contents and the content identifier for each content from the signaling information table, storing contents being downloaded through a FLUTE or an internet in a storage medium, based upon the additional information on contents and the content identifier for each content, and displaying a list of recordings including the contents stored in the storage medium, wherein a list of recordings screen displaying the list of recordings includes at least one of a content name, a channel name, a date of recording, and a content size.

This application is a continuation application of U.S. application Ser.No. 13/632,663 filed on Oct. 1, 2012, which is a continuationapplication of U.S. application Ser. No. 12/688,512 filed on Jan. 15,2010, now U.S. Pat. No. 8,307,393 which issued on Nov. 6, 2012 andclaims the benefit of U.S. Provisional Patent Application No.61/145,104, filed on Jan. 15, 2009, U.S. Provisional Patent ApplicationNo. 61/153,985, filed on Feb. 20, 2009, U.S. Provisional Application No.61/153,973 filed on Feb. 20, 2009, U.S. Provisional Application No.61/160,689 filed on Mar. 16, 2009, U.S. Provisional Application No.61/169,711 filed on Apr. 15, 2009, U.S. Provisional Application No.61/179,005 filed on May 17, 2009, U.S. Provisional Application No.61/226,259 filed on Jul. 16, 2009, U.S. Provisional Application No.61/255,844 filed on Oct. 28, 2009, which are hereby incorporated byreference as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. The Field

The present disclosure relates to a method for processing non-real timeservice and broadcast receiver thereof.

2. Description of the Related Art

A digital television (DTV) can not only provide video and audio serviceswhich are conventional TV services, but can now also provide variousother services. For example, the DTV can provide an Electronic ProgramGuide (EPG) or the like to the user and can simultaneously providebroadcast services received through 2 or more channels. Especially, thenumber of services that a reception system can provide has beensignificantly increased since the reception system has been equippedwith a large-capacity storage device and has been connected to theInternet or data communication channels which enable bidirectionalcommunication.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a method of receivingand processing non-real time services and a broadcast receiver.

Another object of the present invention is to provide a method ofmanaging a storage medium storing non-real time services and a broadcastreceiver.

A further object of the present invention is to provide a method ofindicating non-real time services stored in the storage medium and abroadcast receiver.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, amethod of processing a non-real time service of a broadcast receiverincludes receiving a signaling information table including additionalinformation on contents configuring a non-real time service and acontent identifier for each content, acquiring the additionalinformation on contents and the content identifier for each content fromthe signaling information table, storing contents being downloadedthrough a FLUTE or an internet in a storage medium, based upon theadditional information on contents and the content identifier for eachcontent, and displaying a list of recordings including the contentsstored in the storage medium, wherein a list of recordings screendisplaying the list of recordings includes at least one of a contentname, a channel name, a date of recording, and a content size.

Herein, the contents stored in the storage medium may be categorized asoperator contents being managed by a service provider and user contentsbeing managed by a user.

The method further includes allocating a storage space for the operatorcontents in the storage medium. Herein, a minimum storage space for theoperator contents may be predetermined, and the storage space for theoperator contents within the storage medium may be allocated to belarger than the predetermined minimum storage space. Also, the operatorcontents may not be deleted by the user.

The method further includes setting-up user preference conditionsincluding at least one of gender, age, location, genre, hobby, andpreservation period, and downloading a content satisfying the userpreference conditions through at least one of the FLUTE and theinternet, thereby storing the downloaded content in the storage medium.Herein, the contents of the list of recordings screen may be sortedbased upon at least of the content name, the channel name, the date ofrecording, and the content size, so as to be displayed.

When detailed information on a specific content is requested from thelist of recordings screen, a detailed information screen including atleast one of a content name, a channel name, date and size informationrelated to the content, image information, and text information may bedisplayed. Herein, the detailed information screen may include an AddMemo button, wherein comments on the content may be inputted by the userwhen the Add Memo button is selected, and wherein the comment (or memo)on the content inputted (or added) by the user may be displayed as textinformation. Also, the detailed information screen may include a Protectbutton, wherein a protect function may be activated on the content whenthe Protect button is selected, and wherein the protected content maynot be deleted upon an en bloc deletion request made by the user.

In another aspect of the present invention, a broadcast receiverincludes a tuner and a service manager. Herein, the tuner receives asignaling information table including additional information on contentsconfiguring a non-real time service and a content identifier for eachcontent. And, the service manager acquires the additional information oncontents and the content identifier for each content from the signalinginformation table. Herein, the service manager may store contents beingdownloaded through a FLUTE or an internet in a storage medium, basedupon the additional information on contents and the content identifierfor each content, and may display a list of recordings including thecontents stored in the storage medium, wherein a list of recordingsscreen displaying the list of recordings includes at least one of acontent name, a channel name, a date of recording, and a content size.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 illustrates a conceptual diagram of providing a real-time (RT)service and a non-real time (NRT) service;

FIG. 2 is a diagram illustrating the relationship between an NRTservice, content item, and files;

FIG. 3 illustrates an embodiment of a protocol stack for a fixed NRTservice according to the present invention;

FIG. 4 illustrates an embodiment of a bitstream syntax structure of avirtual channel table according to the present invention;

FIG. 5 illustrates an embodiment of service type field values in thevirtual channel table of FIG. 4 and respective meanings of the values;

FIG. 6 illustrates another embodiment of values allocated to a servicetype field in the virtual channel table of FIG. 4 and respectivemeanings of the values;

FIG. 7 illustrates an embodiment of a bitstream syntax structure of adata service table (DST) of the present invention;

FIG. 8 illustrates an embodiment of a procedure for obtaining accessinformation of an IP stream that carries an NRT service signalingchannel using a PSI/PSIP table according to the present invention;

FIG. 9 is a flowchart illustrating a procedure for obtaining accessinformation of an IP stream that carries an NRT service signalingchannel using a PSI/PSIP table according to an embodiment of the presentinvention;

FIG. 10 and FIG. 11 illustrate a bitstream syntax structure of aNon-Real Time Service Table (NST) according to the present invention;

FIG. 12 illustrates a bitstream syntax structure of acomponent_descriptor( ) according to an embodiment of the presentinvention;

FIG. 13 illustrates a bitstream syntax of FLUTE file delivery data usingthe component_descriptor( );

FIG. 14 and FIG. 15 illustrate a bitstream syntax structure of aNon-Real Time Information Table (NRT-IT) according to an embodiment ofthe present invention;

FIG. 16 and FIG. 17 illustrate an exemplary FDT XML (eXtensible MarkupLanguage) schema according to the present invention;

FIG. 18 illustrates an exemplary storage medium management screen;

FIG. 19 illustrates an exemplary user reference configuration screenaccording to the present invention;

FIG. 20 illustrates a RT-specific service guide screen according to anembodiment of the present invention;

FIG. 21 illustrates an exemplary NRT service guide screen, which can beshifted from the RT-specific service guide screen;

FIG. 22 to FIG. 24 illustrates examples for displaying codec informationof a program according to the present invention in message formats;

FIG. 25 and FIG. 26 respectively illustrate list of recordings accordingto embodiments of the present invention;

FIG. 27 illustrates an exemplary detailed information screen, which isdisplayed when detailed information on a specific content is requestedfrom the list of recordings; and

FIG. 28 illustrates a block view showing a structure of a broadcastreceiver for fixed NRT services according to an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the invention, which can achieve the aboveobjects, will now be described with reference to the accompanyingdrawings. The configuration and operation of the invention, illustratedin the drawings and described below with reference to the drawings, willbe described using at least one embodiment without limiting the spiritand the essential configuration and operation of the invention.

Although most terms of elements in the present invention have beenselected from general ones widely used in the art taking intoconsideration their functions in the invention, the terms may be changeddepending on the intention or convention of those skilled in the art orthe introduction of new technology. Some terms have been arbitrarilyselected by the applicant and their meanings are explained in detail inthe following description as needed. Thus, the definitions of the termsused in the invention should be determined based on the whole content ofthis specification together with the intended meanings of the termsrather than their simple names or meanings.

The term real time (RT) service used in the present invention actuallymeans the real-time service. In other words, it is restricted in time.On the other hand, non-real time (NRT) service refers to non-real time,not RT, service. Thus, NRT service is not restricted in time. Furtherthe data used in NRT service is referred to as NRT service data.

A broadcast receiver according to the present invention receives NRTservice through terrestrial, cable, internet, and the like.

The NRT service is stored in a storage medium of the broadcast receiverand then it is displayed through a display according to a time specifiedby the user or at the user's request. The NRT service is received andstored in a file format according to an embodiment. In an embodiment,the storage medium is an internal HDD attached to the inner part of thebroadcast receiver. In another embodiment, the storage medium may beUniversal Serial Bus (USB) memory or an external HDD connectedexternally with the broadcast receiver.

In order to receive and store the files configuring the NRT service andprovide service to the user, signaling information is needed. Thesignaling information is referred to NRT service signaling informationor NRT service signaling data according to the present invention.

According to the method of receiving IP datagram, NRT service can bedivided into Fixed NRT service and Mobile NRT service. Morespecifically, the Fixed NRT service is provided through fixed broadcastreceiver, and Mobile NRT service is provided through mobile broadcastreceiver.

According to an embodiment of the present invention, Fixed NRT serviceis explained in detail. However, the present invention can also beobviously applied to Mobile NRT service as well.

FIG. 1 illustrates a conceptual diagram of how a RT and an NRT serviceare provided.

The broadcast station, following the conventional method, transmits thecurrent terrestrial broadcast (or mobile broadcast) RT service. At thisjuncture, the broadcast station may provide NRT service using the extrabandwidth or a specific bandwidth left after sending the RT service.Thus, RT service and NRT service are transmitted through a same or adifferent channel. Therefore, a broadcast receiver can be divided intoRT service and NRT service, and in order to provide the user with theNRT service when needed, NRT service signaling information (or NRTservice signaling data) is required. The NRT service signalinginformation (or NRT service signaling data) will be described below indetail.

For example, a broadcast station can transmit broadcast service data inreal time and transmit news clips, weather information, advertisements,push VOD, or the like in non-real time. The NRT service may not onlyprovide such news clips, weather information, advertisements, and pushVOD, but may also provide specific scenes, detailed information onspecific program, preview (trailer) from a real-time broadcast service.

A conventional broadcast receiver (i.e., a legacy device) can receiveand process RT services but cannot receive and process NRT services.Thus, it is a principle that the process of the conventional broadcastreceiver (i.e., a legacy device) is not affected by NRT stream includedin the transmission of RT service. In other words, the conventionalbroadcast receiver does not have a method of handling the NRT serviceeven if it is received.

However, the broadcast receiver (i.e., an NRT device) according to anembodiment of the present invention can combine NRT services and RTservices to provide a variety of services to the user compared to theconvention receiver.

In an embodiment, one NRT service according to the present inventionincludes one or more content item (or content or NRT content) and onecontent item includes one or more files as shown in FIG. 2. The terms“file” and “object” have the same meaning in the description of thepresent invention.

The content item is the minimum unit that can be presentedindependently. For example, when a news program, which includes aneconomic news section, a political news section, and a life newssection, is provided in non-real time, the news program may be an NRTservice and each of the economic news section, the political newssection, and the life news section may be the content item. And each ofthe economic news section, the political news section, and the life newssection may include at least one file.

The NRT service can be transmitted in an MPEG-2 Transport Stream (TS)packet format through a dedicated broadcast channel or the samebroadcast channel as the RT service. In this case, a unique PID istransmitted after being allocated to a TS packet of the NRT service datain order to identify the NRT service. In an embodiment of the presentinvention, IP-based NRT service data is packetized into an MPEG-2 TSpacket for transmission.

The NRT service signaling data required to receive the NRT service datais transmitted through an NRT service signaling channel. The NRT servicesignaling channel is transmitted through a specific IP stream in the IPlayer. Here, the IP stream is also packetized into an MPEG-2 TS packetfor transmission. The NRT service signaling data transmitted through anNRT service signaling channel includes NRT Service Map Table (NST) andNRT Information Table (NRT-IT). In an embodiment of the presentinvention, the NST provides the access information of at least one NRTservice and at least one content item/file that forms NRT services thatoperate in the IP layer. In one embodiment of the present invention,NRT-IT provides detailed information of the content item/file that formsNRT service. In the present invention, the NST and the NRT-IT may bereferred to as Signaling Information Table.

FIG. 3 illustrates a diagram for a protocol stack of an NRT serviceconfigured according to an embodiment of the present invention.

In an embodiment of the present invention, for fixed NRT service, thefile-type NRT service is packetized according to an IP scheme in the IPlayer and then transmitted through a specific virtual channel in anMPEG-2 TS format.

In an embodiment of the present invention, as an example of the MPEG-2based Program Specific Information/Program and System InformationProtocol (PSI/PSIP) table, the presence of the NRT service or theidentification information of the NRT service may be signaled throughthe virtual channel in the Virtual Channel Table (VCT).

In an embodiment of the present invention, the NRT service signalingchannel that transmits NRT service signaling data which signals theaccess information of the IP based NRT service is transmitted in anMPEG-2 TS format after being packetized according to an IP stream in theIP layer through a specific virtual channel.

More specifically, in the broadcast station, NRT content/files arepacketized according to a file transfer protocol scheme and are againpacketized according to an Asynchronous Layered Coding/Layered CodingTransport (ALC/LCT) scheme as shown in FIG. 3. The packetized ALC/LCTdata is again packetized according to an UDP scheme and the packetizedALC/LCT/UDP data is again packetized into ALC/LCT/UDP/IP data accordingto an IP scheme. In the present invention, the packetized ALC/LCT/UDP/IPdata is referred to as an “IP datagram” for ease of explanation.

In addition, NRT service signaling data required to receive the NRTcontent/files is transmitted through an NRT service signaling channel.Here, the NRT service signaling channel is packetized according to aUser Datagram Protocol (UDP) scheme and the packetized UDP data is againpacketized into UDP/IP data according to an IP scheme. In the presentinvention, the UDP/IP data is also referred to as an “IP datagram” forease of explanation. In an embodiment, multicast of the NRT servicesignaling channel is achieved after being encapsulated in an IP datagramhaving a well-known IP destination address and a well-known destinationUDP port number.

In an embodiment of the present invention, IP datagrams of the NRTservice signaling channel and the NRT service are encapsulated in anaddressable section structure and again packetized in an MPEG-2 TSformat. So, one addressable section structure has a format in which asection header and a CRC checksum are added to one IP datagram. Thisaddressable section structure format complies with a Digital StorageMedia Command and Control (DSM-CC) section format for private datatransmission. Thus, the addressable section is also referred to as a“DSM-CC addressable section.” A 188-byte MPEG-2 TS packet can be createdby dividing the addressable section data into 184-byte units and addinga 4-byte MPEG header to each 184-byte unit. At this time, a valueallocated to a PID of the MPEG header is a unique value that canidentify TS packets that carry the NRT service signaling channel and theNRT service.

Program Specific Information (PSI) and Program and System InformationProtocol (PSIP) table section data is also packetized into MPEG-2 TSpackets.

An embodiment of the PSI table may include a Program Map Table (PMT), aProgram Association Table (PAT), or the like and an embodiment of thePSIP table may include a Virtual Channel Table (VCT), a System TimeTable (STT), a Rating Region Table (RRT), an Extended Text Table (ETT),a Direct Channel Change Table (DCCT), a Direct Channel Change SelectionCode Table (DCCSCT), an Event Information Table (EIT), and a MasterGuide Table (MGT).

The MPEG-2 TS packets are modulated according to a predeterminedtransmission scheme, for example, a VSB transmission scheme, in aphysical layer and are then transmitted to the reception system.

In an embodiment of the present invention, the transmission of an NRTservice is determined by signaling through a PSI/PSIP table. Forexample, whether or not an NRT service is transmitted is signaled in aVirtual Channel Table (VCT).

FIG. 4 illustrates a syntax structure of the Virtual Channel Table (VCT)section according to an embodiment.

The VCT section, taking information about the virtual channel forexample, transmits information of channel information for channelselection and PID information for receiving audio and/or video. Thus,when the VCT section is parsed, the PID of the audio and video of thebroadcast program transmitted within the channel along with the channelnumber and channel name is known.

The VCT section syntax includes at least one of table_id field,section_syntax_indicator field, private_indicator field,section_length_field, transport_stream_id field, version_number_field,current_next_indicator field, section_number field, last_section_numberfield, protocol_version field, num_channels_in_section field.

The VCT section syntax further includes first ‘for’ loop (virtualchannel loop) which repeats for the number indicated in thenum_channels_in section field value, the first loop includes at leastone of short_name field, major_channel_number field,minor_channel_number field, modulation_mode field, carrier_frequencyfield, channel_TSID field, program_number field, ETM_location field,access_controlled field, hidden field, service_type field, source_idfield, descriptor_length field, or second ‘for’ loop which repeats forthe number of the descriptors included in the first loop. For theconvenience of explanation in the present invention, the second loop isreferred to as the first descriptor loop. The descriptor( ) included inthe first descriptor loop is a descriptor applied in each virtualchannel.

The VCT section syntax may further include a third ‘for’ loop whichrepeats for the number of value indicated byadditional_descriptor_length field and the number of descriptor added inthe VCT section. For the convenience of explanation in the presentinvention, the third loop is referred to as the second descriptor loop.The additional_descriptors( ) included in the second descriptor loop isapplied to all the descriptors described in the virtual channel of theVCT section.

A table_id field illustrated in FIG. 4 indicates a unique identifier oridentification (ID) which identifies that the information transmittedthrough the table is VCT. More specifically, the table_id fieldindicates a value informing that the table corresponding to this sectionis a VCT. For example, a 0xC8 value may be given to the table_id field.

A version_number field indicates the version number of the VCT, thesection_number field indicates the number of this section, and thelast_section_number field indicates the number of the last section of acomplete VCT. The num_channels_in_section field designates the number ofthe overall virtual channel existing within the VCT section.

A short_name field in the first ‘for’ loop indicates the name of avirtual channel. The major_channel_number field indicates a ‘major’channel number associated with the virtual channel defined within thefirst loop and the minor_channel_number field indicates ‘minor’ channelnumber. Thus, each channel number should be connected to the major andminor channel numbers, and the major and minor channel numbers are usedas user reference numbers for the corresponding virtual channel.

A program_number field is shown for connecting the virtual channelhaving an MPEG-2 program association table (PAT) and program map table(PMT), and matches the program number within the PAT/PMT. Here, the PATdescribes the elements of a program corresponding to each programnumber, and the PAT indicates the PID of a transport packet transmittingthe PMT. The PMT describes the affiliated information and the PID listof the transport packet in which the identification number and theaudio/video information of a program is transmitted in bit sequence.

A service_type field indicates the service type within the correspondingvirtual channel.

In an embodiment, the virtual channel may include at least one RTservice and at least one NRT service including audio and/or video.

In this case, service type values may be allocated as shown in FIG. 5and a value of 0x04 representing an ATSC-data-only service may be usedto indicate that an NRT service is provided through the virtual channel.

In another embodiment, the virtual channel may only include one or moreNRT service. In such a case, as shown in FIG. 6, a new service_typefield value of 0x08 may be defined to indicate that an NRT service isprovided through the virtual channel.

A source_id field indicates a program source connected to thecorresponding virtual channel.

The term “source” refers to a specific source such as a video, text,data or audio source. The source_id field has a unique value in atransport stream in which a VCT is transmitted.

On the other hand, data service table (DST) may be received through PIDincluded in the service_location_descriptor of the VCT, and through theDST, the types of the application and the detailed information of thedata broadcast stream transmitted through the channel is known.

In the present invention, NRT application (NRT service) is identifiedthrough the DST.

FIG. 7 illustrates the DST section syntax structure according to anembodiment.

A sdf_protocol_version field (8-bit) indicates the version of theService Description Framework protocol.

An application_count_in_section field (8-bit) indicates the number ofapplications listed within the DST section.

A compatibility_descriptor( ) field indicates that the correspondingstructure includes DSM-CC compatible descriptor. The object is to signalthe compatibility requests of the application of the platform receivedto determine the ability to use the corresponding data service.

An app_id_byte_length field (16-bit) indicates the number of bytes usedto identify the application.

An app_id_description field (16-bit) indicates the format and thesemantics of the next application identification bytes. As described inthe table 1 below, ‘0x0003’ is newly assigned to identify that thecorresponding application is an NRT application. The assigned value of‘0x0003’ is just an exemplary value and the scope of this application isnot limited to the value.

TABLE 1 Value Application Identifier Format 0x0000 DASE application0x0001 ATSC reserved 0x0002 ATSC A/92 Application 0x0003 NRT Application0x0004-0x7FFF ATSC reserved 0x8000-0xFFFF User private

An app_id_byte field (8-bit) describes the byte of the applicationidentifier.

A tap_count field (8-bit) indicates the number of Tap( ) structure usedby the corresponding application.

A protocol_encapsulation field (8-bit) indicates the type of theprotocol encapsulation used to transmit the specific data element inreference with the Tap( ) field.

An action_type field (7-bit) instructs the character of the data inreference with the Tap( ) field.

A resource_location field (1-bit) indicates the location of theassociation_tag field that matches the association_tag value listedwithin the next Tap structure. If the value of the corresponding fieldis ‘0,’ then the matching association_tag exist in the PMT of thecurrent MPEG-2 program. Oppositely, if the value is ‘1,’ then thematching association_tag exists in the DSM-CC Resource Descriptor in theNetwork Resources Table of the corresponding data service.

A Tap( ) field, for example, is defined in a unique structure includingthe following. The tap_id field (16-bit) is used by the application toidentify the data elements. The range of the value of tap_id isdetermined by the app_id_byte fields related to Tap( ) within the DST.The value of tap_id is selected by the data service provider. Further,it is used in application to handle the data elements.

A Use field (16-bit) is used to specify the communication channelreferenced by the association_tag.

An association_tag field (16-bit) uniquely identifies one from thelisted DSM-CC resource descriptor within the Network Resource Table orlisted data elementary stream within the PMT.

A Selector( ) field indicates a unique data element that can be used inthe communication channel referenced by association_tag field or in thedata elementary stream.

A tap_info_length field (16-bit) indicates the number of bytes of thedescriptors of the next field of the corresponding field.

A tap_info_length field (16-bit) indicates the number of bytes of thedescriptors of the next field of the corresponding field.

An app_info_length field (8-bit) indicates number of bytes of thedescriptor of the next corresponding field.

A descriptor( ) field follows the descriptor format.

An app_data_length field (16-bit) indicates length of the app_data_bytefields in bytes.

An app_data_byte (8-bit) describes the private data fields differentfrom input parameters associated with the application as 1 byte.

A service_info_length field (8-bit) indicates number of byte unit of thenext descriptors.

A descriptor( ) field follows the descriptor format.

A service_private_data_length field (16-bit) indicates length of byteunit of the private fields.

A service_private_data_byte field (8-bit) describes the private fieldsas 1 byte.

FIG. 8 illustrates a method in which an NRT service is received andprovided using an ATSC A/90 standard for carrying (or transmitting) adata broadcast stream and an ATSC A/92 standard for transmitting an IPmulticast stream in a broadcast receiver according to the presentinvention.

Namely, information of a stream that constitutes each virtual channel issignaled in an ES_loop of a PMT or a service location descriptor of aVCT. For example, an NRT service stream can be transmitted through thevirtual channel in the case where the service type of the VCT is 0x02(i.e., digital A/V Data), 0x04 (i.e., data only), or 0x08 (i.e., NRTonly service), as shown in FIG. 5 or FIG. 6. At this time, when thestream_type field included in the service location descriptor (or the ESloop of the PMT) has a value allocated 0x95 (i.e., DST transmission),this indicates that a data broadcast is transmitted. A normal A/V istransmitted if the service location descriptor has no value forstream_type field or does not have a value of 0x95 allocated. Therefore,if the stream_type field included in the service location descriptor hasa value of 0x95, the Elementary_PID field value is a PID of a DataService Table (DST). Thus, the DST can be received through theElementary_PID field.

The type of the application and details of a data broadcast streamtransmitted through this channel can be determined through the DST. Inthe present invention, an NRT application (i.e., an NRT service) isidentified using the DST.

That is, an App_id_description field of the DST specifies the format andanalysis of application identification bytes subsequent to this field.In an embodiment of the present invention, ‘0x0003’ is allocated to theApp_id_description field in order to identify the NRT application. Theillustrated value (number) is only an example and does not limit thescope of the present invention.

If the App_id_description field value is ‘0x0003’, anApplication_id_byte value subsequent to this field is a service ID ofthe NRT application. A service ID of the NRT application may have a URIvalue that globally and uniquely identifies the corresponding service.

After the NRT application is identified as described above, a PID of anMPEG-2 TS packet separated from the IP datagram of the NRT servicesignaling channel is located through the Tap information. Then, an IPdatagram that carries the NRT service signaling channel can be obtainedfrom MPEG-2 TS packets having the PID found through the tap informationand NRT service signaling data can be obtained from the obtained IPdatagram. Here, well-known IP access information, i.e., a well-known IPaddress and a well-known UDP port number can be used as the IP accessinformation of the NRT service signaling channel.

That is, an asynchronous IP stream is transmitted if aProtocol_encapsulation field value in the DST is 0x04 and a device_idvalue indicating the destination address is transmitted through aselector_bytes value if a Selector type field value is 0x0102. Amultiprotocol_encaplsulation_descriptor is used in order to accuratelyanalyze the selector_bytes value and signals the number of valid bytesincluded in the device_id value. As a result, IP multicasts address (oraddress range) of the NRT service signaling channel transmitted throughthe PID can be determined through the Tap information.

Accordingly, the IP multicast address (or address range) is accessed andan IP stream, i.e., an IP packet, is received and NRT service signalingdata is extracted from the received IP packet.

NRT service data, i.e., NRT content/files, is received based on theextracted NRT service signaling data and the received data can be storedin a storage medium or can be displayed on a display.

In another embodiment of the present invention, the NRT service can besignaled using a new value, for example, 0x96 instead of 0x95 as thestream type field value of the DST. This embodiment aims to eliminatethe risk that the conventional receiver may malfunction with the NRTservice which is a new application, in the case where the conventionalreceiver operates by determining whether or not a data broadcast streamis present based only on whether or not a stream having a stream typevalue of 0x95 is present. In this case, if a new stream type is defined,it will be possible to allow the conventional receiver to ignore thisstream type, thereby guaranteeing backward compatibility.

FIG. 9 is a flowchart illustrating the process of NRT service signalingdata and the process of extracting the NRT service data.

In an embodiment, as shown in FIG. 9, the service_type field in the VCThas a value of 0x08 as in FIG. 6, indicating that at least one NRTservice is transmitted through the relevant virtual channel.

After a power of a receiver has been turned on, if a default channel ora channel by a user is selected (S1001), the receiver receives a VCT ora PMT (S1002). And then the receiver determines whether NRT serviceexists or not by parsing the VCT (S1003). This can be done throughlooking at the service_type in the received virtual channel loop withinthe VCT. The (S1001) step is processed in the tuner and the(S1002)/(S1003) step is processed in the PSI/PSIP section handler.

For instance, if a value of the service_type is not set to ‘0x08’, therelevant virtual channel will not transmit NRT service. The virtualchannel will then transmit conventional service (i.e., legacy ATSCservice), the receiver processes according to the information includedin the virtual channel.

If the service_type field has a value of 0x08, the virtual channel willtransmit NRT service. In such a case, service location descriptor in thevirtual channel of the VCT is parsed to extract the PID of DST (S1004).Then, using the extracted PID, DST is received (S1005). The (S1004) and(S1005) step is processed through the demultiplexer controlled by theservice manager.

It is then determined whether the corresponding service provided on theselected channel is an NRT service from the received DST (S1006).

The determination of a presence of the NRT service can be performed bychecking the value of the App_id_description field.

For instance, the value of the App_id_description is set to ‘0x0003,’ inthis present invention to identify that the service is an NRTapplication (i.e., NRT service). The value (number) is only an exampleand will not limit the scope of the present invention.

If the value of the App_id_description field is ‘0x0003,’ the value ofthe subsequent Application_id_byte becomes the value of service ID ofthe NRT application (i.e., NRT service). As a result of identifying theNRT application, a Tap is extracted to locate the PID of the MPEG-2 TSpacket separated from the IP datagram of the NRT service signalingchannel (S1007). And, stream PID including association_tag of the Tap isextracted from the PMT (S1008). The steps of (S1006) to (S1008) areprocessed by the service manager or the PSI/PSIP section handler.

After receiving and decapsulating the MPEG-2 TS packets corresponding tothe stream PID, i.e, removing the MPEG-2 header, a DSM-CC addressablesection is recovered (S1009). This process is handled by the addressablesection handler.

Subsequently, after removing section header and CRC checksum from theDSM-CC addressable section, IP datagram transmitting the NRT servicesignaling channel is recovered (S1010), and the NRT service signalingdata is obtained from the recovered IP datagram (S1011). At this time,the access information of the IP datagram transmitting the NRT servicesignaling channel is received from a well-known destination IP addressand well-known destination UDP port number.

If a value of Protocol_encapsulation in the DST is set to ‘0x04’, anasynchronous IP datagram is transferred. If Selector_type is set to‘0x0102’, a value of device_id indicating a destination address isdelivered via selector_bytes. In order to accurately analyze the valueof the selector_bytes, multiprotocol_encapsulation_descriptor is usedand the number of the valid byte within the device_id is signaled. As aresult, the IP Multicast address (or address range) of the NRT servicesignaling channel transmitted through PID of the Tap information isknown.

Thus, by accessing the IP Multicast address (or address range), IPstream, i.e., IP packet is received, and the NRT service signaling datais extracted from the IP packet.

Based on the extracted NRT service signaling data, NRT service data,i.e., NRT content item/files can be received and stored in a storageunit or can be displayed through a display.

In an embodiment, the NRT service signaling data transmitted through theNRT service signaling channel may include NRT Service Map Table (orService Table: NST) and NRT Information Table (NRT-IT).

In an embodiment, IP datagrams of the NST and NRT-IT has the samewell-known IP address and well-known UDP port number. Therefore, thedetermination of NST and NRT-IT included in the NRT service signalingdata is done through table identifier. Thus, the table identifier can bethe table_id of the corresponding table or the header of the tablesection, and when necessary, table_id_extension can be referred to inorder to identify the table.

NRT Service Map Table (NST)

The NST provides access information of the NRT service. In anembodiment, the NST has a similar table to the MPEG-2 Private sectionformat.

The NST provides access information of IP based NRT services included inthe virtual channel. For example, the NST provides access information ofeach FLUTE sessions that configures one NRT service.

Here, whether one NST is configured with one session or plurality ofsessions is determined through the table_id field, section_number field,last_section_number field, and the like. And the table may be completedby removing the IP header and the UDP header of the IP datagrams of theNRT service signaling channel and gathering sections having the sametable identifier. For example, by gathering the sections having tableidentifier allocated for NST, the NST is completed.

FIG. 10 and FIG. 11 illustrate a bitstream syntax structure of an NSTsection according to an embodiment of the present invention. The detailof each field of the NST section is explained in the following.

Although the syntax is written in an MPEG-2 private section format forbetter understanding, the data may be in any format. For example, it ispossible to use another method in which the syntax is expressed in aSession Description Protocol (SDP) format and is then signaled through aSession Announcement Protocol (SAP).

In FIG. 10 and FIG. 11, a table_id field includes an 8-bit unsignedinteger number that indicates the type of table section being defined inNRT Service Table (NST).

A section_syntax_indicator is a 1-bit field that shall be set to ‘0’ toalways indicate that this table is derived from the “short” form of theMPEG-2 private section table.

A private_indicator (1-bit) indicates whether the type of thecorresponding section follows the private section type or not. (Thisfield that shall be set to ‘1’)

A section_length is a 12-bit field. It specifies the number of remainingbytes this table section immediately following this field. The value inthis field shall not exceed 4093 (0xFFD)).

A table_id_extension field is a 16-bit field and is table-dependent. Itshall be considered to be logically part of the table_id field providingthe scope for the remaining fields. The table_id_extension fieldincludes NST_protocol_version fields.

The NST_protocol_version field is an 8-bit unsigned integer field whosefunction is to allow, in the future, this NST to carry parameters thatmay be structured differently than those defined in the currentprotocol. At present, the value for the NST_protocol_version field shallbe zero. Non-zero values of NST_protocol_version may be used by a futureversion of this standard to indicate structurally different tables.

A version_number field (5-bit) indicates the version number of the NST.

A current_next_indicator field is a one-bit indicator, which when se to‘1’ shall indicate that the NST sent is currently applicable. When thebit is set to ‘0’, it shall indicate that the table sent is not yetapplicable and will be the next table to become valid. This standardimposes no requirement that “next” tables (those withcurrent_next_indicator set to ‘0’) must be sent. An update to thecurrently applicable table shall be signaled by incrementing theversion_number field).

A section_number field is an 8-bit field that shall give the sectionnumber of this NST section. The section_number field of the firstsection in an NST shall be ‘0x00’. The section_number field shall beincremented by 1 with each additional section in the NST.

A last_section_number field is an 8-bit field that shall give the numberof the last section (i.e., the section with the highest section_number)of the NST of which this section is a part).

A num_NRT_services field is an 8-bit field that specifies the number ofservices in this NST section.

A ‘for’ loop, which is also referred to as an “NRT service loop”, isexecuted for the number of times as the number of NRT servicescorresponding to the num_NRT_services field value in providing signalinginformation of a plurality of NRT services. Thus, signaling informationof the corresponding NRT service is indicated for each of the NRTservices included in the NST section. Here, the following fieldinformation may be provided for each NRT service.

An NRT_service_id field is a 16-bit unsigned integer number that shalluniquely identify this NRT service within the scope of this NRT section.The NRT_service_id field of a service shall not change throughout thelife of the service. To avoid confusion, it is recommended that if aservice is terminated, then the NRT_service_id field for the serviceshould not be used for another service until after a suitable intervalof time has elapsed.

An NRT_service_status field is a 2-bit enumerated field that shallidentify the status of this NRT Service. The most significant bit shallindicate whether this NRT Service is active (when set to ‘1’) orinactive (when set to ‘0’) and the least significant bit shall indicatewhether this NRT Service is hidden (when set to ‘1’) or not (when set to‘0’). Hidden services are normally used for proprietary applications,and ordinary receiving devices should ignore them.

A SP_indicator field is a 1-bit field that indicates when set to 1,service protection is applied to at least one of the components neededto provide a meaningful presentation of this NRT Service.

A Short_NRT_service_name_length field (3-bit) instructs the number ofbyte pairs within the Short_NRT_service_name field.

A Short_NRT_service_name filed (16*m bit) indicates a short name of theNRT service. This field may be filled with null data (for example, 0x00)when the NRT service has no short name.

An NRT_service_category field is a 6-bit enumerated type field thatshall identify the type of service carried in the NRT.

A num_components field is a 5-bit field that specifies that number of IPstream components in this NRT Service.

An IP_version_flag is a 1-bit indicator, which when set to ‘0’ shallindicate that source_IP_address, NRT_service_destination_IP_address, andcomponent_destination_IP_address fields are IPv4 addresses. The value of‘1’ for this field is reserved for possible future indication thatsource_IP_address, NRT_service_destination_IP_address, andcomponent_destination_IP_address fields are for IPv6.

A source_IP_address_flag field is a 1-bit Boolean flag that shallindicate, when set, that a source IP address value for this NRT Serviceis present to indicate a source specific multicast.

An NRT_service_destination_IP_address_flag field is a 1-bit Boolean flagthat indicates, when set to ‘1’, that anNRT_service_destination_IP_address field value is present, to serve asthe default IP address for the components of this NRT Service.

A source_IP_address field is a 32 or a 128 bit field that shall bepresent if the source_IP_address_flag field is set to ‘1’ and shall notbe present if the source_IP_address_flag field is set to ‘0’. Ifpresent, this field shall contain the source IP address of all the IPdatagrams carrying the components of this NRT Service. The conditionaluse of the 128 bit-long address version of this field is to facilitatepossible use of IPv6 in the future, although use of IPv6 is notcurrently defined.

An NRT_service_destination_IP_address field is a 32 or a 128 bit fieldthat shall be present if the NRT_service_destination_IP_address_flagfield is set to ‘1’ and shall not be present if theNRT_service_destination_IP_address field is not present, then thecomponent_destination_IP_address field shall be present for eachcomponent in the num_components loop. The conditional use of the 128bit-long address version of this field is to facilitate possible use ofIPv6 in the future, although use of IPv6 is not currently defined.

A ‘for’ loop, which will also be referred to as a “component loop,” isexecuted as much as the number of times as the number of componentscorresponding to the num_components field value to provide accessinformation of a plurality of components. This provides accessinformation of each component included in the NRT service. Here, thefollowing field information may be provided for each component. In anembodiment, one component corresponds to one FLUTE session.

An essential_component_indicator field is a 1-bit indicator which, whenset to ‘1’, shall indicate that this component is an essential componentfor the NRT Service. Otherwise, this field indicates that this componentis an optional component.

A port_num_count is a 6-bit field that shall indicate the number ofdestination UDP ports associated with this UDP/IP stream component. Thevalues of the destination UDP port numbers shall start from thecomponent_destination_UDP_port_num field and shall be incremented byone.

A component_destination_IP_address_flag field is a 1-bit Boolean flagthat shall indicate, when set to ‘1’, that thecomponent_destination_IP_address field is present for this component.

A component_destination_IP_address field (32 or 128 bit) shall bepresent if the component_destination_IP_address_flag field is set to ‘1’and shall not be present if the component_destination_IP_address_flagfield is set to ‘0’. When this field is present, the destination addressof the IP datagrams carrying this component of the NRT Service shallmatch the address in this field. When this field is not present, thedestination address of the IP datagrams carrying this component shallmatch the address in the NRT_service_destination_IP_address field. Theconditional use of the 128 bit-long address version of this field is tofacilitate possible use of IPv6 in the future, although use of IPv6 isnot currently defined.

A component_destination_UDP_port_num field is a 16-bit unsigned integerfield that represents the destination UDP port number for this UDP/IPstream component.

A num_component_level_descriptors field (4-bit) indicates the number ofdescriptors providing the additional information of the component level.

The same number of the component_level_descriptor( ) is included in thecomponent loop providing additional information as the number of thefield value of the num_component_level_descriptors.

A num_NRT_service_level_descriptors field (4-bit) indicates the numberof descriptors that provide additional information about the NRT servicelevel.

The same number of the NRT_service_level_descriptor( ) are included inNRT service loop as the number of the field value ofnum_NRT_service_level_descriptors to provide additional informationabout the NRT service.

A num_virtual_channel_level_descriptors field (4-bit) indicates thenumber of descriptors which provides additional information about thevirtual channel level.

The same number of virtual_channel_level_descriptor( ) included in thevirtual channel loop as the number of the field value of thenum_virtual_channel_level_descriptors to provide additional informationof the virtual channel.

FIG. 12 illustrates an embodiment of a bitstream syntax structure of acomponent_level_descriptors( ). The component_descriptor( ) is used asone of the component level descriptor component_level_descriptors( ) ofthe NST and describes additional signaling information of thecorresponding component.

The following is a description of each field of thecomponent_descriptor( ).

In FIG. 12, a descriptor_tag field (8-bit) is a descriptor identifierand it can be set as an identifier that identifies thecomponent_descriptor( ).

A descriptor_length field (8-bit) describes the remaining length of thedescriptor starting after the descriptor_length field and to the end ofthis descriptor, in bytes.

A component_type field (7-bit) shall identify the encoding format of thecomponent. The value may be any of the values assigned by IRNA for thepayload_type of an RTP/AVP stream, or it may be any of the valuesassigned by ATSC, or it may be a “dynamic value” in the range 96-127.For components consisting of media carried via RTP, the value of thisfield shall match the value in the payload_type field in the RTP headerof the IP stream carrying this component. Note that additional values ofthe component_type field in the range of 43-71 can be defined in futureversions of this standard.

A component_encryption flag (1-bit) informs whether the correspondingcomponent is encrypted or not.

A Num_STKM_streams field (8-bit) indicates the number STKM streams ifcomponent_encryption_flag has been encrypted. (The num_STKM_streamsfield (8-bit) is an 8-bit unsigned integer field that shall identify thenumber of STKM streams associated with this component.

A STKM_stream_id field (8-bit) is repeated as much as the field value ofNum_STKM_streams and indicates a value that identifies a STKM streamthat can acquire a key required for decryption.

An NRT_component_data (component_type) element provides the encodingparameters and/or other parameters necessary for rendering thiscomponent. The structure of the component_data is determined by thevalue of component_type field.

For example, if the component_type field value is 35 thenNRT_component_data (component_type) field provides component data forH.264/AVC video stream.

In another example, if the component_type field value is 38 thenNRT_component_data (component_type) field provides data for FLUTE filedelivery as shown in FIG. 13.

One NRT service can be included in multiple FLUTE sessions. Thus, oneNRT service may be configured with plurality of FLUTE sessions. EachFLUTE session may be signaled using NRT_component_data( ) as shown inFIG. 13.

FIG. 13 illustrates an example of the bitstream syntax structure ofNRT_component_data( ) that provides data for FLUTE file deliveryaccording to the present invention. The following explains each field inthe NRT_component_data( ).

A TSI field (16-bit unsigned integer) shall be the Transport SessionIdentifier (TSI) of FLUTE session.

A session_start_time field (16-bit) indicates the start time of theFLUTE session. If the field values are all ‘0’, then it can beinterpreted that the FLUTE session has already begun.

A session_end_time field (16-bit) indicates the end time of the FLUTEsession. If the field values are all ‘0,’ then it can be interpretedthat the FLUTE session continues for unlimited amount of time.

A tias_bandwidth_indicator field (1-bit) flags the inclusion of TIASbandwidth information. This bit shall be set to ‘1’ to indicate the TIASbandwidth field is present, and it shall be set to ‘0’ to indicate theTIAS bandwidth field is absent.

An as_bandwidth_indicator field (1-bit) flags the inclusion of ASbandwidth information. This bit shall be set to ‘1’ to indicate the ASbandwidth field is present, and it shall be set to ‘0’ to indicate theAS bandwidth field is absent.

A FEC_OTI_indicator field (1-bit) indicates whether FEC ObjectTransmission Information is provided.

A tias_bandwidth field (16-bit) exists when the as_bandwidth_indicatorfield value is set to ‘1’ and it indicates the maximum bandwidth. Also,it shall be one one-thousandth of the Transport Independent ApplicationSpecific maximum bandwidth as defined in RFC 3890, rounded up to thenext highest integer if necessary. This gives the TIAS bandwidth inkilobits per second.

An as_bandwidth field (16-bit) exists when the as_bandwidth_indicatorfield value is set to ‘1’ and it indicates the maximum AS bandwidth.Also, this value shall be the Application Specific maximum bandwidth asdefined in RFC 4566. This gives the AS bandwidth in kilobits per second.

A FEC_encoding_id field exits when the FEC_OTI_indicator field value isset to ‘1’ and indicates FEC ID used in corresponding FLUTE session.(FEC encoding ID used in this FLUTE session, as defined in RFC 3926).

A FEC_instance_id field exists when the FEC_OTI_indicator field value isset to ‘1’ and indicates FEC instance ID used in the corresponding FLUTEsession. (FEC instance ID used in this FLUTE session, as defined in RFC3926).

The information necessary to receive FLUTE session is provided bysignaling the parameters through the NRT_component_data( ) of thecomponent_descriptor( ) within the component loop.

In other words, according to the time information set by thesession_start_time field and the session_end_time field, thecorresponding FLUTE session is opened and files and the FDT (FileDescription Table) that describes the signaling information of the filesthat configures NRT service (or content) is received. The FDT is used totransmit the list of all the content items, and also providesinformation necessary in acquiring content item and the files includedin the content item.

For example, each file configuring a content item may be identified byusing a Content-Location indicated in an FDT of a FLUTE session. TheContent-Location indicates an identifier that can identify thecorresponding file. Herein, the Content-Location is configured in ananyURI (Uniform Resource Identifier) format. More specifically, theContent-Location value is a locator including the file name.

At this point, a content linkage identifying the corresponding contentitem may be allocated (or assigned) for each file level or instancelevel of the FDT. In this case, each file may be identified by usingcontent linkage, transfer object identifier (TOI), and Content-Locationvalues indicated in the FDT of the FLUTE session. Herein, the contentlinkage corresponds to an identifier that can identify the content item,and the TOI corresponds to an identifier that can identify a transportobject, i.e., file being transmitted through the FLUTE session. Forexample, when the TOI value is equal to ‘0’, the file corresponds to theFDT. More specifically, the TOI value of each file configuring thecontent item is greater than ‘0’.

NRT Information Table (NRT-IT)

FIGS. 14 and 15 are bitstream syntax of an NRT-IT section according toan embodiment of the present invention.

The bit-stream syntax of the NRT-IT section is described in MPEG-2Private section format for ease of understanding the bit-stream syntaxof the NRT-IT section, but the format of the data can be in otherformats as well. For example, signaling through Session AnnouncementProtocol (SAP) described by Session Description Protocol (SDP) type isalso possible.

An NRT-IT of NRT service signaling data according to an embodiment ofthe present invention includes information describing a downloadablecontent item to store a content item in a broadcast receiver.

Here, the determination whether one NRT-IT is configured through onesection or plurality of sections can be known through the table_idfield, section_number field, last_section_number field, and the like,within the NRT-IT section. And the table may be completed by removingthe IP header and the UDP header of the IP datagrams of the NRT servicesignaling channel and gathering sections having the same tableidentifier. For example, by gathering the sections having tableidentifier allocated for NRT-IT, the NRT-IT is completed.

The detailed description of the NRT-IT section fields illustrated inFIGS. 14 and 15 are described below.

A table_id field (8-bit) is set to 0xTBD to identify this table sectionas belonging to the Non-Real-Time Information Table.

A service_id field (16-bit) specifies the service_id field associatedwith the NRT service offering content items described in this section.

An NRT_IT_version_number field (5-bit) indicates the version number ofthis NRT-IT instance, where NRT-IT instance is defined as the set of oneor more NRT_information_table_section( ) having common values forservice_id field, current_next_indicator field, protocol_version field,and time_span_start field. The version number is incremented by 1 modulo32 when any field in the NRT-IT instance changes.

A current next indicator field (1-bit) is always set to ‘1’ for NRT-ITsections; the NRT-IT sent is always currently applicable.

A protocol_version field (8-bit) is set to zero. The function ofprotocol_version field is to allow, in the future, this table type tocarry parameters that may be structured differently than those definedin the current protocol. At present, the only valid value forprotocol_version field is zero. Non-zero values of protocol_versionfield may be used by a future version of this standard to indicatestructurally different tables.

A time_span_start field (32-bit) represents the start of the time spancovered by this instance of the NRT-IT, expressed as the number of GPSseconds since 00:00:00 UTC, Jan. 6, 1980. The time of day oftime_span_start field is aligned to minute 00 of the hour. The valuezero for time_span_start field indicates the time period covered by hisNRT-IT instance began in the indefinite past. The value oftime_span_start field is the same for each section of a multi-sectionedNRT-IT instance. The values of time_span_start field andtime_span_length field are set such that the specified time span doesnot overlap with any other NRT-IT instance in this IP subnet.

A time_span_length field (11-bit) indicates the number of minutes,starting at the time indicated by time_span_start field, covered by thisinstance of the NRT-IT. Once established, the value of time_span_lengthfield for a given value of time_span_start field does not change. Avalue of time_span_length field of zero means this NRT-IT instancecovers all time starting at time_span_start field into the indefinitefuture. If the value of time_span_start is zero, time_span_length fieldhas no meaning. The value of time_span_length field is the same for eachsection of a multi-sectioned NRT-IT instance. The values oftime_span_start field and time_span length field are set such that thespecified time span does not overlap with any other NRT-IT instance inthis IP subnet.

A num_items_in_section field (8-bit) indicates the number of contentitems described in this NRT-IT section.

The ‘for’ loop (also referred to as content item loop) is executed fornumber of content items corresponding to the value of thenum_items_in_section field and provides signaling information aboutplurality of content items. Thus, the signaling information of thecontent item of each content item included in the NRT servicecorresponding to the service_id field value is indicated. The followingdescribes the field in each content item that may provide theinformation.

The content_linkage field is a 32-bit field having a value ranging from0x0001 to 0xFFFF. The content_linkage field indicates an identificationnumber of the corresponding content (or content item). Herein, the value0x0000 is not used. The content_linkage field performs two linkagefunctions. One linkage function is to link the metadata included in anNRT-IT with at least one or more files included in an FLUTE FDT, whichis associated with the NRT service. The other linkage function is toform a TF_id field, i.e., an identifier for a Text Fragment in a TextFragment Table. The value of the content_linkage field corresponds toone of the values of the FDT-Content-Linkage elements or to one of thevalues of the File-Content-Linkage elements within the FLUTE FDT foreach of the files associated with the content item. The precedence rulesmay be applied when matching each content_linkage value with thecorresponding content linkage elements in the FLUTE FDT.

An updates_available field (1-bit) indicates whether the correspondingcontent item is updated. For example, when the content item is includedin an NRT service that is ended after once service, the field is set to‘0’. When the content item is one more updated, the field is set to ‘1’.That is, the updates_available field specifies, when set to ‘1,’ thatthe referenced content item(s) will be updated. When theupdates_available field is set to ‘0,’ updates are not expected to beprovided for the associated content item(s), and broadcast receivers arenot expected to look for them.

A TF_available field is Boolean flag, this field specifies, when set to‘1’ that a Text Fragment is present in a Text Fragment Table in theservice signaling channel. When the field is set to ‘0,’ no TextFragment is included in the service signaling channel for this contentitem.

A low_latency field is Boolean flag, this field specifies, when set to‘1,’ that the content is available within the current digital transportwith a low enough latency that its retrieval should be attempted whilethe user waits. When the field is set to ‘0’, retrieval latency islonger and the user interface should suggest to the user to return laterfor viewing.

A playback_length_in_seconds field (20-bit) specifies the duration ofplayback of the content, in seconds. For content consisting only of textand/or still images, the value zero is used. For content that includesaudio or audio/video content, the playback_length_in_seconds fieldindicates the playback length of the audio or audio/video content.

A content_length_included field is Boolean flag, this field indicates,when set to ‘1,’ that the content_length field is present in thisiteration of the “for” loop. Setting this field to ‘0’ indicates thecontent_length field is not present in this iteration of the “for” loop.

A playback_delay_included field is Boolean flag, this field indicates,when set to ‘1,’ that the playback_delay field is present in thisiteration of the “for” loop. Setting this field to ‘0’ indicates theplayback_delay field is not present in this iteration of the “for” loop.

An expiration_included field is Boolean flag, this field indicates, whenset to ‘1,’ that the expiration field is present in this iteration ofthe “for” loop. Setting this field to ‘0’ indicates the expiration fieldis not present in this iteration of the “for” loop.

A duration field (12-bit) in the range 1 to 2880 specifies the expectedcycle time, in minutes, of the carousel containing the referencedcontent item. A broadcast receiver is expected to use the durationparameter to determine the amount of time needed to capture thereferenced content.

A content_length field (40-bit), when present, represents the total sizein bytes of the content item or items. This item is used by thebroadcast receiver to determine if enough memory is available to storeit before downloading is attempted.

A playback_delay field (20-bit) counts of the number of secondsfollowing reception of the first byte of the associated content thebroadcast receiver waits before playback may start, while buffering theincoming stream. A value of zero indicates playback may commenceimmediately. When playback_delay field is not provided, the broadcastreceiver is expected to retrieve the complete file or file set prior toplayback.

An expiration field is a 32-bit field, which indicates an expirationtime of the corresponding content.

A content_name_length field is an 8-bit field, which indicates the totallength of the subsequent content_name_text( ) field in byte units. Thecontent_name_text( ) field specifies a title of a corresponding content(or content item) in a multiple string structure (MSS).

A content_descriptors_length field is a 12-bit field, which indicatesthe total length of the subsequent content_descriptor( ) field in byteunits.

The content_descriptor( ) field corresponds to a descriptor providingadditional information on a content level, the content_descriptor( )field being individually applied to each content (or content item).

A descriptors_length field is a 10-bit field, which indicates the totallength of the subsequent descriptor( ) field in byte units.

The descriptor( ) field is commonly applied to all contents (or contentitems) being described in the current NRT-IT section.

Also, according to an embodiment of the present invention, information(or parameter) essentially required for rendering content/files, whichconfigure the NRT service, e.g., encoding information and decodingparameters applied to the video, audio, and so on, included in an NRTservice or content, is transmitted to the broadcast receiver. Forexample, the encoding information may correspond to codec information ofthe video and audio included in the NRT service or content.

The encoding information and decoding parameter may be signaled throughan in-line field of the descriptor, thereby being transmitted, or may besignaled through an in-line field of the NST or NRT-IT, thereby beingtransmitted. At this point, the descriptor is included in any one of aFLUTE session level or NRT service level, or component level or contentlevel.

Also, according to an embodiment of the present invention, the encodinginformation and decoding parameter are provided in text formatsexpressed as a multi-purpose Internet mail extensions (MIME) type. Morespecifically, the broadcast receiver according to the present inventionindicates and transmits the encoding information and decoding parameterin a text format.

Meanwhile, an NRT service according to the present invention includes atleast one or more contents (or content items or NRT contents), as shownin FIG. 2, and one content includes at least one or more files.

And, the files included in the content are provided to the NRT throughthe FLUTE session. However, the files included in the content may beprovided not only through the FLUTE session, but also through theInternet.

At this point, according to an embodiment of the present invention,Internet access information of the content is provided through a contentlevel descriptor of the NRT-IT. In the description of the presentinvention, the corresponding descriptor will be referred to as aninternet location descriptor internet_location_descriptor( ). Theinternet location descriptor includes a URL( ) field, which indicatesthe internet URL of the content.

Also, according to another embodiment of the present invention, anindicator field indicating whether or not the content is also beingprovided through (or available on) the internet is added to the NRT-ITfield. In the description of the present invention, the field is thiscase will be referred to as an available_on_internet field. When thevalue of the available_on_internet field indicates that thecorresponding content is available on the internet, the Content_Locationattribute within the FLUTE FDT corresponding to each file that belongsto the content indicates the internet URL of the file.

More specifically, when the value of the available_on_internet fieldwithin the content loop of the NRT-IT indicates that the correspondingcontent is available on the internet, the Content_Location attribute ofeach file within the FLUTE FDT indicates the internet address of thecorresponding file.

If the internet access information is provided through the internetlocation descriptor, the available_on_internet field may be omitted fromthe NRT-IT of FIG. 14 and FIG. 15.

FIG. 16 and FIG. 17 respectively illustrate an exemplary FDT XML(eXtensible Markup Language) schema according to the present invention.

According to FIG. 16 and FIG. 17, when an attribute is required to becommonly defined in all files declared in the FDT (or FDT instance), anFDT instance level is defined, and when an attribute is required to beindependently defined in each file, an FDT file level is defined.

Referring to FIG. 16 and FIG. 17, the portion marked as number 1corresponds to a declaration of a content linkage in an FDT instancelevel. The content linkage declared herein is given to all filesdeclared in the corresponding FDT instance. Evidently, this informationmay be overridden by newly giving a content linkage from the file level.Alternatively, when a specific file belongs not only to the content (orcontent item) defined in the FDT instance level but also to anothercontent, the content linkage may be given from the file level, which isthen notified.

The portion marked as number 2 corresponds to a declaration of a contentlinkage in a file level. Herein, when the files included in the FDTinstance belong to different contents, this method is used to signal thecontent to which each file belongs.

The portion marked as number 3 corresponds to a method of notifying foreach file whether or not the corresponding file is an entry file. Morespecifically, among the plurality of files configuring the content, afile corresponding to a root file, which must be reproduced first, orwhich must be executed first in order to access the content, is referredto as an entry file. Herein, an entry attribute may be omitted, and whenthe default value is set to ‘false’ and is omitted, this indicates thatthe corresponding file is not an entry file.

As described above, by signaling each entry status in the file leveldepending upon the group to which the corresponding file belongs, aspecific file may perform an entry function in a specific group and maynot perform any entry function in other groups.

Also, in the file level marked as number 2, one file element providesadditional information by using one or more attributes. Referring toFIG. 16 and FIG. 17, one file element uses Content-Location, TOI,Content-Length, Transfer-Length, Content-Type, Content-Encoding,Content-MD5, FEC-OTI-FEC-Encoding-ID, FEC-OTI-FEC-Instance-ID,FEC-OTI-Maximum-Source-Block-Length, FEC-OTI-Encoding-Symbol-Length,FEC-OTI-Max-Number-of-Encoding-Symbols attributes, so as to providelocation information, TOI, length information, type information,encoding information, etc., on the corresponding file.

When the file element of FIG. 16 and FIG. 17 corresponds to a filebelonging to a content available on the internet, the present inventionincludes the internet address in the Content-Location attribute valuemarked as number 4. For example, the Content-Location attribute withinthe FLUTE FDT corresponding to each file belonging to the content itemindicates the internet URL of the corresponding file. More specifically,in this case, the Content-Location attribute limits the type of the fileto ‘Internet URL’.

As described above, the content may be downloaded through the FLUTEsession, or may be downloaded through the internet. The contentdownloaded through the FLUTE session or through the internet is storedin a storage medium based upon the settings of the broadcast receiver, adownload reservation request, and so on. Additionally, a real-timecontent (i.e., A/V packet) is also stored in storage medium based uponany one of the temporary recording, reserved recording, time-shiftrequests. In the description of the present invention, the content beingdownloaded through the FLUTE session and stored will be referred to asan NRT content, and the content being downloaded through the FLUTEsession and stored will be referred to as a web content, for simplicity.Also, a real-time content being stored based upon any one of thetemporary recording, reserved recording, time-shift requests will bereferred to as a PVR content. At this point, the NRT content, the webcontent, and the PVR content may each be stored in a different storagemedium, or may all be stored in the same storage medium.

The NRT content, web content, and PVR content, which are stored in thestorage medium, are managed by the user. More specifically, each contentmay be deleted from the storage medium upon request made by the user. Inthe description of the present invention, the contents being managed bythe user, including the NRT content, the web content, and the PVRcontent, will be collectively referred to as user contents, forsimplicity.

Meanwhile, some contents may be managed by an operator (e.g., theservice provider). In the description of the present invention, suchcontents will be referred to as operator contents. The operator contentscorrespond to targeted advertisements, announcements (or notices)provided by the service provider, and so on. The operator contents arenot controlled by the user. For example, the user is unable to directlydelete the operator contents from the storage medium.

As described above, each type of contents may be classified asOperator-controlled contents, which are controlled by the operator, andUser-controlled contents, which are controlled by the user.

Furthermore, a space for storing the operator contents should beallocated in the storage medium.

The storage space for the operator contents may be automaticallyallocated based upon the total capacity of the storage medium, or adefault capacity may be allocated regardless of the stored size.

According to an embodiment of the present invention, the user maymanually allocate the storage space for the operator contents through aset-up screen. For this, the broadcast receiver according to the presentinvention includes a menu enabling a storage space of the operatorcontents to be set-up.

FIG. 18 illustrates an example of a storage medium management screenbeing displayed based upon a selection made from a storage mediummanagement menu according to the present invention.

Referring to FIG. 18, the total space of the storage medium is 35 GB.And, herein, the storage space for the operator contents is 0.1 GB, thestorage space for the NRT contents is 10 GB, the storage space for thePVR contents is 15 GB, and the storage space for the web contents is 9.9GB.

As shown in FIG. 18, an Up button is used for expanding (or increasing)the capacity of a selected storage space item, and a Down button is usedfor reducing (or decreasing) the capacity of the selected storage spaceitem. Also, a change quota is used for allocating the storage spacemodified by the Up/Down button as the final storage space.

At this point, according to an embodiment of the present invention, theminimum storage space for the operator contents is pre-decided, and theuser is unable to allocate the storage space from the operator contentsto a size smaller than the pre-decided minimum storage space (or minimumspace).

Also, the user should be aware (or informed) of the minimum space forthe operator contents. For example, as shown in FIG. 18, when anoperator usage item is selected, the minimum space may be informed in atext format at one portion of the set-up screen. More specifically, byselecting an operator usage item, the user may set up the storage spacefor the operator contents. For example, according to the presentinvention, when the Up button is selected from the bottom side of theset-up screen, while the operator usage item is high-lighted, theoperator storage space is increased, and when the Down button isselected, the operator storage space is decreased.

At this point, once the operator storage space becomes the minimumstorage space due to the Down button, the storage space no longerbecomes smaller no matter how many times the Down button is pressedafterwards. The remaining storage space, for example, the storage spacefor the NRT contents, PVR contents, and web contents, may be directlyallocated by the user, or the remaining storage space may beautomatically allocated by the broadcast receiver depending upon thecapacity of the storage medium.

Also, in FIG. 18, the storage medium for each of the NRT contents, thePVR contents, and the web contents is independently managed. However, atleast two types of contents may be combined so as to be managed in asingle storage space.

In the present invention, the operator may provide a differentiatedservice depending upon the size of the storage space for the operatorcontents allocated by the user. For example, depending upon the size ofthe storage space for the operator contents, a subscription fee may bedifferently charged or the usage fee may be differently charged.

Also, when the storage space is managed from the storage mediummanagement screen, the present invention may set-up a preferencecondition for each storage space. According to an embodiment of thepresent invention, the present invention may further display a Menubutton for user preference configuration on a portion of the storagemedium management screen of FIG. 18.

FIG. 19 illustrates an exemplary user preference configuration screen,while the operator usage item is high-lighted.

FIG. 19 shows an example of inputting configuration settings such as‘Male’ for Gender, ‘20˜30’ for Age, ‘Seoul, Korea’ for Location, ‘Soccerand Basketball’ in ‘Sports’ and ‘Show’ for Genre, ‘Camera’ for Hobby,and ‘18 Months’ for validation period (‘Delete contents if older than’)of the corresponding content (i.e., storage period of the content).

As described above, when the user preference conditions are set-up, themanagement of the operator contents is automatically executed inaccordance with the inputted settings. For example, among the contentsprovided by the operator, only the operator contents that satisfy theuser preference conditions may be automatically stored in the storagemedium. Alternatively, when a two-way (or bi-directional) communicationis available between the server of the operator and the broadcastreceiver, the user preference condition set-up in the broadcast receiveris transmitted to the server of the operator. Thereafter, the server ofthe operator may transmit only the contents satisfying the userpreference conditions to the corresponding broadcast receiver.

In another example, among the contents provided from the operator, thebroadcast receiver may use a text or icon to notify the user of thecontents satisfying the user preference conditions. Then, the user mayselect whether or not to download the corresponding content based uponthe notified information.

Then, when it is assumed that the operator contents corresponding to theuser preference condition is stored in the storage medium, when a periodof 18 months is completed starting from the date at which the operatorcontent was downloaded, the operator content is automatically deletedfrom the storage medium.

As described above, the present invention provides a user preferenceconfiguration screen for filtering targeted advertisements, which are tobe stored in the storage space of the operator contents, and for rulesetting en bloc deletion of the operator contents. Herein, the user mayinput adequate parameters through the user preference configurationscreen.

The operations of the broadcast receiver according to the userpreference configuration may also be directly applied to differentcontents, such as NRT contents, PVR contents, and web contents, withoutmodification.

Meanwhile, when using a service guide, the user may easily performselecting, storing (i.e., recording) operations on the NRT contents, webcontents, and PVR contents. In the description of the present invention,a service guide for the PVR contents will be referred to as anRT-specific service guide, and a service guide for the NRT contents andweb contents will be referred to as an NRT-specific service guide, forsimplicity. Also, in the description of the present invention, a screenconfigured of the RT-specific service guide will be referred to as anRT-specific service guide screen, and a screen configured of theNRT-specific service guide will be referred to as an NRT-specificservice guide screen, for simplicity.

At this point, the RT-specific service guide and the NRT-specificservice guide may be simultaneously displayed on a single screen. Or,any one of the RT-specific service guide and the NRT-specific serviceguide may only be displayed on the screen. In addition, the RT-specificservice guide screen may be shifted to the NRT-specific service guidescreen, or the NRT-specific service guide screen may be shifted to theRT-specific service guide screen.

In the present invention, the RT-specific service guide screen may beimplemented by using a PSI/PSIP table, and the NRT-specific serviceguide screen may be implemented by using an NRT service signalingchannel. For example, schedule information of a PVR content may beacquired from an event information table (EIT) from the PSI/PSIP table.And, among the NRT service signaling channels, schedule information ofan NRT content and a web content may be acquired from the NRT-IT.

FIG. 20 illustrates an exemplary RT-specific service guide screenaccording to the present invention.

In FIG. 20, the title of a program (i.e., content) that is currentlyserved through a current RT based upon a current time, or the title of aprogram (i.e., content) that is to be served through an RT in a futureprocess is displayed for each broadcast station (i.e., channel).According to an embodiment of the present invention, a button thatallows the screen to shift to the NRT-specific service guide screen isdisplayed on a portion of the RT-specific service guide screen. In thedescription of the present invention, this button will be referred to asa “View previous program” button, for simplicity.

FIG. 21 illustrates an exemplary NRT service guide screen, which can bedisplayed when the “View previous program” button is selected from theRT-specific service guide screen of FIG. 20.

According to an embodiment of the present invention, a button thatallows the screen to shift to the RT-specific service guide screen isdisplayed on a portion of the NRT-specific service guide screen. In thedescription of the present invention, this button will be referred to asa “View current program” button, for simplicity.

The NRT-specific service guide screen of FIG. 21 corresponds to anexample wherein programs that were broadcasted in the past arecategorized, for example, by genre and displayed. Herein, according toan embodiment of the present invention, the genre information of eachprogram is provided through a genre descriptor included in a servicelevel of the NST or a content level of the NRT-IT. Also, since it isassumed in the NRT-specific service guide screen that each programcorresponds to a previous program, the actual broadcasting time of eachprogram may also be displayed. At this point, the downloadable time ofeach program may also be displayed. According to another embodiment ofthe present invention, the previously broadcasted programs may also becategorized by channel, by broadcasted date, and by title, thereby beingdisplayed on the NRT-specific service guide screen.

The RT-specific service guide screen and the NRT-specific service guidescreen of FIG. 20 and FIG. 21 are merely examples provided to facilitatethe understanding of the present invention. Therefore, since theconfiguration of the RT-specific service guide screen and theNRT-specific service guide screen may be easily modified by anyoneskilled in the art, the present invention will not be limited only tothe examples given in the description set forth herein.

When a program satisfying the user preference condition exists among theprograms displayed on the service guide screens of FIG. 20 and FIG. 21,the present invention may notify the presence of such program to theuser by using a text or an icon. More specifically, it is assumed thatJunior Soccer of FIG. 20 and Professional Baseball of FIG. 21 bothsatisfy the user preference condition set-up in the user preferenceset-up screen of FIG. 19. According to an embodiment of the presentinvention, both the Junior Soccer and the Professional Baseball aremarked with a smile icon, as shown in FIG. 20 and FIG. 21.

At this point, the programs marked with smile icons may be automaticallystored in the storage medium. Alternatively, the programs marked withsmile icons may be used for reference purposes to allow the user toeasily recognize his (or her) preferred programs.

Herein, in the NRT-specific service guide screen, as shown in FIG. 21,when the user uses an input means, such as a remote controller, akeyboard, a mouse, a touch pad, and so on, to select a specific program,a sub-menu (or a sub pop-up window) enabling the user to select “PlayNow” or “Schedule Advance Recording” in accordance with the attributesof the respective program, is displayed. FIG. 21 shows an example of asub-menu screen enabling the user to select at least one of “Play Now”and “Schedule Advance Recording”, when the user selects a programentitled “Heroes Episode 5”.

Also, when additional information related to the selected program isserved via NRT, an additional information button may be displayed on thesub-menu screen in the form of a text or icon, so as to allow the userto recognize the presence of the additional information and select thecorresponding information. At this point, when the additionalinformation button is selected, the corresponding additional informationis provided to the user. The additional information corresponds topreviews (or recaps), watch full episodes, music video, original soundtrack (OST) related to the program.

When several additional information related to the program exist, anadditional information list may be displayed, so as to provide specificadditional information selected from the additional information list tothe user.

According to an embodiment of the present invention, even if the programavailable for “Play Now” and the program available for “Schedule AdvanceRecording” correspond to the same program, if the resolution of the twoprograms is different, the resolution information of each program isindicated next to each program by using a text format or an icon,thereby enabling the user to recognize the difference in resolution andto select the preference program.

According to another embodiment of the present invention, in case of aprogram that is neither available for “Play Now” nor for “ScheduleAdvance Recording”, even if a cursor (or high-light) is placed on thecorresponding program within the service guide screen, the correspondingprogram is inactivated, so that the user cannot select the correspondingprogram. More specifically, even if the corresponding program isselected, a related sub-menu is not displayed. However, if at least oneof “Play Now” and “Schedule Advance Recording” is available, then therelated sub-menu is displayed.

Meanwhile, when the user selects the “Play Now” item from the sub-menuscreen of the NRT-specific service guide screen shown in FIG. 21, thecorresponding program may be pre-stored in the storage medium (e.g.,HDD, flash memory) of the respective broadcast signal or may be directlyprovided from the internet.

If the program available for “Play Now” is a program being provided froma web server through an internet access (i.e., web contents), theinternet access information of the program may be acquired through theabove-described internet location descriptor, or may be acquired throughcontent-location attributes of the corresponding files of the FLUTE FDT,which belongs to the content corresponding to the program.

Furthermore, when the user selects the “Schedule Advance Recording”item, the files that belong to the content respective to the selectedprogram are downloaded through the FLUTE session at a predeterminedtime, so as to be stored in the storage medium of the respectivebroadcast receiver. Thereafter, the stored files are immediatelyoutputted or outputted upon the user's request to an output device, soas to be displayed. Then, once the downloading of the program iscompleted, an identification information that can identify thecompletion of the downloading process may be marked in a portion of theRT service screen or marked on the corresponding program within theNRT-specific service guide screen in the form of a text or icon, therebynotifying the user that the downloading process is completed.

According to an embodiment of the present invention, a program beingdownloaded from a web server through the internet is stored in a webcontents storage space of the storage medium. And, a program beingdownloaded through the FLUTE session is stored in an NRT contentsstorage space. At this point, the web contents storage space and the NRTcontents storage space may be differentiated in the same storage medium,or may be differentiated in different storage medium.

Meanwhile, in some occasions, the program downloaded via “Play Now” orthe program downloaded via “Schedule Advance Recording” may not beplayed-back by the broadcast receiver. In this case, playback may not beperformed for many reasons. One of the reasons corresponds to when acodec for decoding the program does not exist in the broadcast receiver.The presence of a codec for decoding the corresponding program in thebroadcast receiver may be known by using at least one of the encodinginformation and the decoding parameter, which are received in a MIMEtype text form through the NST or NRT-IT. The encoding information mayinclude codec information used in the video stream of the correspondingprogram, codec information used in the audio stream of the correspondingprogram, and so on. Also, the MIME type encoding information may beprovided by being inserted in the NST or NRT-IT in a field format, ormay be provided by being inserted in a descriptor format. For example,it is assumed that a text indicating “The video codec used in Program Ais A2” is included in the encoding information as a MIME type. However,if the video codec A2 is not installed in the broadcast receiver, thebroadcast receiver is incapable of playing-back the correspondingprogram. At this point, it is also assumed that neither the video codecA2 nor any other backward compatible codec is installed.

At this point, according to an embodiment of the present invention,since playback cannot be performed even if the program is downloaded, amessage is displayed so as to allow to user to acknowledge thesituation. Herein, according to an embodiment of the present invention,the message is displayed in the form of a pop-up window.

For example, it is assumed that a download schedule is reserved in thesub-menu screen and that a video codec for the program scheduled fordownloading is not installed in the respective broadcast receiver. Inthis case, based upon the transmitted MIME-type encoding information anddecoding parameter, the broadcast receiver may create codec informationof the selected program, as shown in FIG. 22, which is then displayed inthe form of a pop-up window. Alternatively, the broadcast receiver mayalso generate a message saying “The video codec required for decodingProgram A does not exist in this broadcast receiver.” or “The videocodec required for decoding Program A does not exist in this broadcastreceiver. Do you wish to download the required video codec?” or “Thevideo codec required for decoding Program A is A2.”

The message is then displayed in the form of a pop-up window. Suchmessage may also be applied when the playback option of a downloadedprogram is selected.

FIG. 23 and FIG. 24 illustrates examples of a message that can bedisplayed in the form of a pop-up window, when playback cannot beperformed due to the absence of a codec required playing-back adownloaded program in the broadcast receiver. According to an embodimentof the present invention, the message is created based upon the encodinginformation and decoding parameter, which are displayed as a MIME-typetext.

In the example shown in FIG. 23, the broadcast receiver displays amessage saying “Due to the absence of the video codec, Program A cannotbe played.” This message allows the user to recognize the reason why thecorresponding program cannot be played (or played-back).

In the example shown in FIG. 24, the broadcast receiver displays amessage saying “Due to the absence of the video codec, Program A cannotbe played. Do you wish to download the required video codec?” Herein,buttons indicating “Yes” and “No” are also displayed so as to enable theuser to select download.

When the user selects the button saying “Yes”, then the required videocodec is downloaded. The video codec may be provided through an NRTservice or may be provided from a web server through the internet.

At this point, the downloaded video codec may be automatically installedin the respective broadcast receiver, or may be installed upon theuser's request.

Meanwhile, when the user wishes to know what kind (or type) of contentis stored in the storage medium, or when the user wishes to playback aspecific content, the user may refer to the list of recording from themenu screen so as to select the corresponding content.

Based upon the request made by the user, when displaying the list ofrecordings, the present invention may display the list of recording invarious methods.

For example, the list of recordings may be included in the entirecontents stored in the storage medium. Also, when requesting the list ofrecordings, the user may select the storage space in which the list ofrecordings is to be included. For example, when it is assumed that thestorage space is divided as shown in FIG. 18, and when the user hasselected the NRT contents storage space and the web contents storagespace, among the contents stored in the storage medium, only the NRTcontents and the web contents are included in the list of recordings,thereby being displayed.

At this point, the list of recordings screen may include at least one ofa content name, channel name, stored date, and content size.

FIG. 25 illustrates an example of a list of recordings being displayedon the screen, wherein the list of recordings includes only the contentsstored in the NRT contents storage space according to the presentinvention.

The list of recordings screen of FIG. 25 includes the content name, thechannel name, the stored date, and the content size. In this example,the contents stored in the NRT contents storage space are sorted anddisplay by order of content size.

For example, the content name may be obtained from thecontent_name_text( ) field of the NRT-IT, and the channel name may beobtained from the short_NRT_service_name field of the NST. Also, therecorded data (validation period) may be obtained from at least one ofthe date when the actual recording was performed in the broadcastreceiver, the duration field of the NRT-IT, the playback_delay field,and the expiration field. The content size may be obtained from thecontent_length field of the NRT-IT.

At this point, a simple version and a detailed version may exist for theoutput screen of the list of recordings. According to an embodiment ofthe present invention, in the simple version, at least one or more ofthe content name, channel name, date of recording (or stored date), andcontent size are displayed, as shown in FIG. 25.

The present invention may display a plurality of execution buttons (ormenu buttons) on the list of recordings screen and may execute commandson view details, delete, and copy options for the corresponding contentfrom the list of recordings.

For example, in the list of recordings of FIG. 25, the Up button is usedfor moving the high-lighted marked on a specific content in an upwarddirection, and the Down button is used for moving the high-lightedmarked on a specific content in a downward direction. The View Detailsbutton is used for viewing the detailed information on the high-lightedcontent. The Delete button is used for deleting the high-lightedcontent. And, the Copy button is used for copying (or moving) thehigh-lighted content to another storage medium (e.g., USB memory)through an outside interface. Herein, the copying of the content mayrequire an authentication process depending upon the copyright,encryption status of the content, and, in some cases, the copying toanother storage medium may not be processed.

The present invention may be set-up so that a specific content cannot bedeleted by an en bloc deletion command. For example, the user may set-upa protect option on the specific content, and the content configuredwith the protect option setting cannot be deleted even when an en blocdeletion command is inputted. According to an embodiment of the presentinvention, the protect settings and the disablement of the protectsetting for a specific content can be configured (or executed) in thedetailed information screen of the corresponding program.

Also, according to an embodiment of the present invention, when ahigh-lighted content is selected, or when a Play button (not shown) isselected, the playback of the selected content is performed.

According to another embodiment of the present invention, when ahigh-lighted content is selected, the detailed information of theselected content may be displayed.

According to an embodiment of the present invention, the list ofrecordings screen provides a sorting function. Firstly, when the list ofrecordings is displayed on the display screen, each content is sorted inan increasing order or decreasing order, based upon items configured indefault settings or items pre-configured by the user in the broadcastreceiver. And, when the list of recordings screen is displayed, aspecific key of an input means, such as a remote controller, or any oneof the items is selected so as to perform the sorting function in thelist of recordings screen. For example, when key number 1 of an inputmeans, such as a remote controller, is pressed, the contents displayedin the list of recordings may be sorted by content name, and when keynumber 2 is pressed, the contents displayed in the list of recordingsmay be sorted by channel name. When key number 3 is pressed, thecontents displayed in the list of recordings may be sorted by date ofrecording, and when key number 4 is pressed, the contents displayed inthe list of recordings may be sorted by content size. At this point, inorder to allow the user to recognize the function of each key, thefunction of each key may be indicated in the form of a text or icon at aportion of the list of recordings screen.

In another example, each time the content name item is selected from thelist of recordings screen, the contents of the list of recordings may besorted by content name in an increasing order or in a decreasing order.Each time the channel name item is selected from the list of recordingsscreen, the contents of the list of recordings may be sorted by channelname in an increasing order or in a decreasing order. Also, each timethe date of recording item is selected from the list of recordingsscreen, the contents of the list of recordings may be sorted by date ofrecording in an increasing order or in a decreasing order. And, eachtime the content size item is selected from the list of recordingsscreen, the contents of the list of recordings may be sorted by contentsize in an increasing order or in a decreasing order.

Furthermore, in the list of recordings screen, a check box is providedat the left-end side of each content item, and deletion and copying maybe performed for at least one or more contents with a single executioncommand. For example, when the check box for each of content 2, content4, and content 6 are checked, and when the Delete button is selectedafterwards, content 2, content 4, and content 6 may be simultaneouslydeleted from the storage medium by a single deletion command. Similarly,when the check box for each of content 2, content 4, and content 6 arechecked, and when the Copy button is selected afterwards, content 2,content 4, and content 6 may be simultaneously copied to another storagemedium by a single copy command.

FIG. 26 illustrates another exemplary display of a list of recordingsincluding only the contents stored in the NRT contents storage spaceaccording to the present invention. Firstly, each content stored in theNRT contents storage space is sorted by channel, and then the contentsof a specific channel are sorted by the date of recording.

In the example shown in FIG. 26, the contents included in the channelnamed ‘KBS’ are sorted by the date of recording, thereby beingdisplayed.

If the user selects the channel named ‘MBC’ from the list of recordingsscreen of FIG. 26, only the contents included in channel MBC aredisplayed on the list of recordings screen. Such description may beidentically applied to other channels.

Referring to FIG. 26, since the undescribed details of FIG. 26 and thefunctions of each button are identical to those described in FIG. 25, adetailed description of the same will be omitted for simplicity.

The list of recordings screen shown in FIG. 25 and FIG. 26 are mereexamples given to facilitate the understanding of the present invention.And, since the configuration of the list of recordings screen may beeasily modified by anyone skilled in the art, the present invention willnot be limited only to the examples given in the description of thepresent invention. Furthermore, the number of execution buttonsdisplayed in the list of recordings screen, shown in FIG. 25 and FIG.26, and their significance are also mere examples given to facilitatethe understanding of the present invention. Therefore, since theaddition or deletion of the execution buttons may be easily modified andaltered by anyone skilled in the art, the present invention will not belimited only to the examples given in the description of the presentinvention.

FIG. 27 illustrates an exemplary detailed information screen, which isdisplayed when detailed information on a specific content is requestedfrom the list of recordings, as shown in FIG. 25 or FIG. 26. In thedetailed information screen of FIG. 27, detailed information on theselected content and execution buttons (or menu buttons) that canexecute management functions are displayed.

The detailed information screen of FIG. 27 is broadly categorized into acontent name area, a channel name area, a content additional informationarea, an image area, and a text data area. The content name areaindicates the name of the content requesting the detailed information.The channel name area may display a channel name to which the contentbelongs, or may display logo of the channel to which the contentbelongs. The content additional information area may indicate a date ofrecording, validation period, content size, and so on, of the content.The image area may indicate a preview, poster, thumbnail images, and soon. And, the text data area may indicate information, such as thesummary (or synopsis), director's intentions, characters, on thecontent. Also, the text data area may also indicate text data, such as auser-added-comment and memo, on the corresponding content.

Furthermore, among the execution buttons shown in FIG. 27, an Add Memobutton is used for enabling the user to directly input a comment or memoon the content. According to an embodiment of the present invention, thecomment or memo inputted by the user is displayed in the text data areaif the detailed information screen. The Delete button is used fordeleting the content, and the Copy button is used for copying thecontent to another storage medium (e.g., USB memory) through an outsideinterface. Herein, the copying of the content may require anauthentication process depending upon the copyright, encryption statusof the content, and, in some cases, the copying to another storagemedium may not be processed. The Protect/Unprotect button is used forsetting or cancelling a protect option setting on the content. Forexample, when a protect option is set-up by using the Protect/Unprotectbutton, the content cannot be deleted by an en bloc deletion commandmade by the user.

The detailed information screen shown in FIG. 27 is mere an examplegiven to facilitate the understanding of the present invention. And,since the configuration of the detailed information screen may be easilymodified by anyone skilled in the art, the present invention will not belimited only to the examples given in the description of the presentinvention. Furthermore, the number of execution buttons displayed in thedetailed information screen, shown in FIG. 27, and their significanceare also mere examples given to facilitate the understanding of thepresent invention. Therefore, since the addition or deletion of theexecution buttons may be easily modified and altered by anyone skilledin the art, the present invention will not be limited only to theexamples given in the description of the present invention.

In the above description, a method of managing a storage medium storingNRT contents and a method of displaying a list of recordings on thecontents stored in the storage medium have been described in detailbased upon a fixed NRT service. However, it is apparent that this methodcan be applied to a mobile NRT service.

More specifically, a signaling information table for the mobile NRTservice according to the present invention include a service map table(SMT). Also, an OMA BCAST service guide is used to provide contentdetailed information. The SMT is in correspondence with the NST of thefixed NRT service, and the OMA BCAST service guide is in correspondencewith the NRT-IT of the fixed NRT service.

The SMT provides real-time services or non-real time services includedin the mobile broadcast program and received and also provides accessinformation of the component (or component item) included in eachservice.

Also, by using the SMT and the OMA BCAST service guide, the list ofrecordings of the NRT contents stored in the storage medium may becreated and displayed on the display screen.

Since reference may be made to the fixed NRT service for the method ofmanaging a storage medium and a method of displaying a list ofrecordings in the mobile NRT service, detailed description of the samewill be omitted for simplicity.

FIG. 28 illustrates a block view showing a structure of a broadcastreceiver for fixed NRT services according to an embodiment of thepresent invention.

The broadcast receiver in FIG. 28 includes an Operation Controller 100,a Baseband processor 110, a Service Demultiplexer 120, a Streamcomponent handler 130, a Media Handler 140, a File Handler 150, aService Manager 160, a PVR Manager 170, a first storage unit 180, an SGHandler 190, an EPG Manager 200, an NRT Service Manager 210, anApplication Manager 220, a MiddleWare Engine 230, a Presentation Manager240, a UI Manager 250, and an internet network interface (260).

The Baseband processor 110 includes a Tuner 111 and a Demodulator 112.The Service Demultiplexer 120 includes an MPEG-2 TP Handler 121, aPSI/PSIP Handler 122, a Demultiplexer 123, a Descrambler 124 and asecond storage unit 125.

The Stream component handler 130 includes a Packetized Elementary Stream(PES) decoder 131, an Elementary Stream (ES) decoder 132, a PCR Handler133, an STC Handler 134, a DSM-CC Addressable Section Handler 135, an IPDatagram Handler 136, a Descrambler 137, a UDP Handler 138, a ServiceSignaling Section Handler 138-1, and a Conditional Access System (CAS)139.

The Media Handler 140 includes an A/V Decoders 141. The File Handler 150includes an ALC/LCT Stream Handler 151, a File Reconstruction Buffer152, an XML Parser 153, an FDT Handler 154, a Decompressor 155, a thirdstorage unit 156, and a File Decoder 157.

The Tuner 111 for example in FIG. 28 detects signal transmitted over theterrestrial system with the control from the Service Manager 160 andtunes only the wanted channel, down converts to Intermediate Frequency(IF), and outputs to the Demodulator 112. The Tuner 111 may receive bothreal time stream and non-real time stream. In the present invention,non-real time stream is referred to as NRT stream.

The Demodulator 112 receives digital IF signal of pass bandwidthinputted from the Tuner 111 and performs automatic gain control,reconstructs carrier frequencies and timing to convert into basebandsignal and equalizes the channel. For example, if the broadcast signalis a VSB modulated signal, a VSB demodulation process is executed forautomatic gain control, and reconstructs carrier frequencies and timing.In the Demodulator 112, demodulated and equalized channel data isoutputted to the MPEG-2 TP Handler 121 in a MPEG-2 Transport Stream (TS)packet format.

The MPEG-2 TP Handler 121 is configured of an MPEG-2 TP Buffer and anMPEG-2 TP Parser, temporarily stores the Demodulator 112 output and thenanalyzes TS Header, and outputs to the Demultiplexer 123 if theDemodulator 112 output is a real time A/V TS packet or NRT TS packet andoutputs to the PSI/PSIP Handler 122 if the output is a TS packet forPSI/PSIP table.

The PSI/PSIP Handler 122 is configured of a PSI/PSIP Section Buffer anda PSI/PSIP Parser, and temporarily stores the outputted TS packet fromthe MPEG-2 TP Handler 121 to reconstruct the corresponding table fromPSI/PSIP Section data included in the payload of TS packet withreferencing table identifier and then parse it. At this time, it ispossible to find out whether one table is configured by one section orplurality of sections by the table_id field, section_number field, andlast_section_number field within the corresponding section. Further,completing the corresponding table is possible by gathering sectionshaving identical table identifiers. For example, it is possible tocomplete a VCT by gathering the sections having table identifiersallocated to VCT. Also, each of the parsed table information iscollected by the Service Manager 160 and then stored in the firststorage unit 180. The VCT, PAT, PMT, DST, EIT, ETT and the like, arestored in the first storage unit 180 after going through the process.The Service Manager 160 stores the table information in the firststorage unit 180 in the Service Map & Guide DB format.

The Demultiplexer 123 divides audio TS packet and video TS packet andthen outputs to the PES Decoder 131 if the TS packet is real time A/V TSpacket and outputs to the DSM-CC Handler 135 if it is an NRT TS packet.Also, the Demultiplexer 123 outputs to the PCR Handler 133 if the TSpacket includes Program Clock Reference (PCR) and outputs to the CAS 139if the TS packet includes Conditional Access (CA) information. The NRTTS packet is divided into TS packet including NRT service data and TSpacket including NRT service signaling channel. A unique PID isallocated to identify the NRT service in the TS packet of the NRTservice data and the PID of the TS packet including the NRT servicesignaling channel is extracted using DST and PMT.

The Demultiplexer 123 outputs to the Descrambler 124 if the payload ofthe inputted TS packet is scrambled and the Descrambler 124 receivesdescrambling information needed for descrambling (for example, controlword used in scrambling) from the CAS 139 and performs descrambling ofthe TS packet.

The Demultiplexer 123 stores A/V packet of real time like a PVR contentfrom any one of the record, timed-record, or time shift request in thesecond storage unit 125. The second storage unit 125 is a mass storagedevice, an example of it can be a HDD. The download (storage) and upload(playing) in the second storage unit 125 is controlled by the PVRManager 170 or the Service manager 160.

At this point, operator contents, such are managed by an operator (e.g.,the service provider) may also be stored in the second storage unit 125.For this, the user may use a storage medium management screen, as shownin FIG. 18, to allocate a storage space for the operator contents withinthe storage space of the second storage unit 125. The operator contentscorrespond to targeted advertisements, announcements (or notices)provided by the service provider, and so on.

At this point, a minimum storage space for the operator contents ispre-decided in the second storage unit 125, and the user cannot allocatethe storage space from the operator contents to a size smaller than thepre-decided minimum storage space (or minimum space). Since referencemay be made to FIG. 18 for the description of the process of allocatingthe operator storage space, detailed description of the same will beomitted for simplicity.

Also, the NRT contents and the web contents according to the presentinvention may be stored in the second storage unit 125 or may be storedin the third storage unit 256. According to an embodiment of the presentinvention, the NRT contents and the web contents are stored in the thirdstorage unit 256. In this case, the total storage space (e.g., 35 GB)shown in the storage medium management screen of FIG. 18 corresponds tothe added sum of the storage space of the second storage unit 125 andthe storage space of the third storage unit 256.

Meanwhile, the operator contents may also be stored in the third storageunit 256 instead of the second storage unit 125. At this point, the usermay use the storage medium management screen of FIG. 18, so as toallocate a storage space for the operator contents within the storagespace of the third storage unit 256. Similarly, a minimum storage spacefor the operator contents is pre-decided in the third storage unit 256,and the user cannot allocate the storage space from the operatorcontents to a size smaller than the pre-decided minimum storage space(or minimum space).

Also, when the storage space is managed from the storage mediummanagement screen, the present invention may set-up a preferencecondition for each storage space. According to an embodiment of thepresent invention, the present invention may further display a Menubutton for user preference configuration on a portion of the storagemedium management screen of FIG. 18. FIG. 19 illustrates an exemplaryuser preference configuration screen, while the operator usage item ishigh-lighted.

In accordance with a playback request, the demultiplexer 123 separatesan audio TS packet and a video TS packet from an A/V TS packet (i.e.,PVR contents) uploaded from the second storage unit 125, therebyoutputting the separated TS packets to a PES decoder 131.

The Demultiplexer 123, in order to perform such functions, is controlledby Service Manager 160 and/or PVR Manager 170.

Thus the Service Manager 160 receives DST by extracting the PID of theDST from the service location descriptor (or ES loop of PMT) of the VCTwhen the service_type field value indicates that NRT service istransmitted.

Further, NRT service is identified through the received DST, andextracts DST and PMT by using the PID of MPEG-2 TS including NRT servicesignaling channel. The extracted PID is outputted to the Demultiplexer123. The Demultiplexer 123 outputs to the Addressable Section Handler135 the MPEG-2 TS packets corresponding to PID outputted by the ServiceManager 160.

The PCR is a standard time value used in syncing audio ES and video ESin the A/V Decoder 141. The PCR Handler 133 outputs to STC Handler 134reconstructed PCR included in the payload of the inputted TS packet. TheSTC Handler 134 outputs to the A/V Decoder 141 reconstructed System TimeClock (STC) which is the standard clock from the system by the PCR.

The PES Decoder 131 is configured with a PES Buffer and a PES Handler,temporarily stores audio TS packet and video TS packet and removes TSheader from each TS packet and reconstructs to audio PES and video PES.The reconstructed audio PES and video PES is outputted to the ES Decoder132. The ES Decoder 132 is configured with an ES Buffer and an ESHandler, removes each PES header from audio PES and video PES andreconstructs audio ES and video ES which are pure data.

The A/V Decoder 141 uses each decoding algorithms to decode the audio ESand video ES and reconstructs to pre-compressed status and then outputsto the Presentation Manager 240. At this point, depending on the STC,the time sync is executed when audio ES and video ES are decoding. Inone example, the audio decoding algorithm may apply at least one of AC-3decoding algorithm, MPEG 2 audio decoding algorithm, HE AAC decodingalgorithm, AAC SBR decoding algorithm, AAC+ decoding algorithm, HE AACdecoding algorithm, AAC SBR decoding algorithm, MPEG surround decodingalgorithm, or BSAC decoding algorithm, and the video decoding algorithmmay apply at least one of MPEG 2 video decoding algorithm, MPEG 4 videodecoding algorithm, H.264 decoding algorithm, SVC decoding algorithm,and VC-1 decoding algorithm.

The CAS 139 is configured with a CA Stream Buffer and a CA StreamHandler, and the TS packet outputted from the MPEG-2 TP Handler 121 orthe service protection data reconstructed and outputted from the UDPDatagram Handler 138 is temporarily stored and then reconstruct theneeded information (control word used in scrambling) to descramble thestored TS packet or the service protected data. Thus, the CAS 139acquires necessary information to descramble after extracting theEntitlement Management Message (EMM) and Entitlement Control Message(ECM) included in the payload of the TS packet, and then by analyzingthe extracted EMM and ECM. The ECM may include the Control Word (CW)used in scrambling. The CW may be encrypted using the authenticationkey. The EMM may include authentication key of the corresponding dataand the requirements information. The acquired information necessary fordescrambling from the CAS 139 will be outputted to the Descramblers 124,137.

The DSM-CC Section Handler 135 is configured with a DSM-CC SectionBuffer and a DSM-CC Section Parser, temporarily stores the TS packetoutputted from the Demultiplexer 123 and then reconstructs theaddressable section included in the payload of the TS packet, andoutputs to the IP Datagram Handler 136 after removing the header and theCRC checksum from the addressable section and then reconstructing the IPDatagram. The IP Datagram Handler 136 is configured with an IP DatagramBuffer and an IP Datagram Parser, and after buffering the IP datagramdelivered from the DSM-CC Section Handler 135, extracts and analyzes theheader of the buffered IP datagram and then outputs to the UDP DatagramSection Handler 138 after reconstructing the UDP datagram from thepayload of the IP datagram.

At this point, if the IP datagram is scrambled, the scrambled UDPdatagram is descrambled in the Descrambler 137 and then outputted to theUDP Datagram Handler 138. In one example, the Descrambler 137 gathersinformation needed for descrambling (for example, control words neededfor scrambling) from the CAS 139 and descrambles the UDP datagram andthen outputs to the UDP Datagram Handler 138.

The UDP Datagram Handler 138 is configured with UDP Datagram Buffer andUDP Datagram Parser, and after buffering the UDP datagram outputted fromthe IP Datagram Handler 136 or the Descrambler 137, extracts andanalyzes the header of the buffered UDP datagram and reconstructs thedata included in the payload of the UDP datagram. At this point, if thereconstructed data is service protection data then it is outputted tothe CAS 139 and if it is NRT service signaling data, then it isoutputted to the service signaling section handler 138-1, and if it isNRT service data then it is outputted to the ALC/LCT stream handler 151.

In an embodiment, the access information of the IP datagram transmittingNRT service signaling channel is a well-known destination IP address andwell-known destination UDP port number.

Therefore, the IP Datagram Handler 136 and UDP Datagram Handler 138 haswell-known destination IP multicast address and well-known destinationUDP port number, and the IP multicast stream which transmits NRT servicesignaling channel, extracts the NRT service signaling data and outputsto the Service Signaling Section Handler 138-1.

Additionally, the service signaling section handler 138-1 is configuredof a service signaling section buffer and a service signaling sectionparser. Herein, the service signaling section handler 138-1 recovers andparses NST, as shown in FIG. 10 and FIG. 11, and NRT-IT, as shown inFIG. 14 and FIG. 15, from the NRT service signaling data, therebyoutputting the processed data to a service manager 160. When the NST isparsed, access information of a FLUTE session, which transmitscontents/files configuring the NRT service, may be obtained. Theinformation parsed from the NST and the NRT-IT is collected (orgathered) by the service manager 160, thereby being stored in the firststorage unit 180. The service manager 160 stores the informationextracted from the NST and the NRT-IT in the first storage unit 180 inthe form of a service map and a service guide. According to anotherembodiment of the present invention, the function (or role) of theservice manager 160 may be performed by an NRT service manager 210. Morespecifically, the information parsed from the NST and the NRT-IT may becollected (or gathered) by the NRT service manager 210, so as to bestored in the first storage unit 180.

Furthermore, when the user requests a service guide screen through a UImanager 250, the service manager 160 or the NRT service manager 210displays an RT-specific service guide screen, as shown in FIG. 20, byusing the information stored in the first storage unit 180, based uponthe control of the operation controller 100. At this point, when theuser uses an input means, such as a remote controller, a keyboard, amouse, a touch pad, and so on, to select a “View previous program” atthe upper portion of the RT-specific service guide screen, theRT-specific service guide screen is shifted to an NRT-specific serviceguide screen, as shown in FIG. 21. Herein, in order to return to thecurrent broadcast, a “View current program” button is provided at theupper portion of the displayed NRT-specific service guide screen.

Even if the program available for “Play Now” and the program availablefor “Schedule Advance Recording” correspond to the same program, if theresolution of the two programs is different, the service manager 160 orthe NRT service manager 210 displays (or indicates) resolutioninformation of each program next to each program by using a text formator an icon, thereby enabling the user to recognize the difference inresolution and to select the preference program. At this point, if theprogram available for “Play Now” is a program being provided from a webserver through an internet access (i.e., web contents), the internetaccess information of the program may be acquired through theabove-described internet location descriptor, or may be acquired throughcontent-location attributes of the corresponding files of the FLUTE FDT,which belongs to the content corresponding to the program. Also, when acodec, which is to be applied to a program that is to be downloaded viaNRT or to a program that is already downloaded, does not exist, theservice manager 160 or the NRT service manager 210 creates a messageupon reference to the transmitted MIME-type encoding information anddecoding parameters, thereby displaying the created message.

Thereafter, a program, content, and additional information beingprovided via NRT, and which are scheduled for downloading, aredownloaded at a predetermined time through the FLUTE session. At thispoint, the downloaded program, content, and additional information passthrough a file decoder 157 so as to be stored in the third storage unit156, or the downloaded program, content, and additional information aredisplayed on the display screen through a presentation manager 240.

At this point, when the program, content, and additional information arebeing downloaded, the NRT service manager 210 may be able to notify theuser whether downloading has not begun yet, or whether downloading is inprogress, or whether downloading has been completed, by using letters,icons, colors, and so on, so that the user can be aware of thedownloading status.

Meanwhile, when the user requests for a list of recordings, particularlya list of recordings related to the NRT contents, through the UI manager250, based upon the control of the operation controller 110, the servicemanager 160 or the NRT service manager 210 uses the information storedin the first storage unit 180 so as to display the list of recordingsscreen, as shown in FIG. 25 or FIG. 26. At this point, in each list ofrecordings screen, the user may perform a function of sorting thecontents by any one of the channel name, date of recording, contentsize, and content name. Also, the user may request detailed informationon a specific content. FIG. 27 illustrates a detailed information screenbeing displayed, when detailed information on a specific content isrequested by the user from the list of recordings screen of FIG. 25 orFIG. 26. Herein, since FIG. 25 to FIG. 27 have already been described indetail in the above description, detailed description of the same willbe omitted for simplicity.

The ALC/LCT Stream Handler 151 is configured with an ALC/LCT StreamBuffer and an ALC/LCT Stream Parser and after buffering the ALC/LCTstructure data outputted from the UDP Datagram Handler 138, analyzes theheader and the header extension of the ALC/LCT session buffered from thedata. After analyzing the header and the header extension of the ALC/LCTsession, if the data transmitted through ALC/LCT session is in XMLstructure then it is outputted to the XML Parser 153, and if the data isin file structure, it is temporarily stored in the File ReconstructionBuffer 152 and outputted to the File Decoder 157 or stored in the thirdstorage unit 156. If the data transmitted through ALC/LCT session isdata for NRT service, the ALC/LCT stream handler 151 gets controlled bythe NRT service manager 210. If the data transmitted through ALC/LCTsession is compressed, the Decompressor 155 decompresses and outputtedto the XML Parser 153, the File Decoder 157, or the third storage unit156.

The XML Parser 153 analyzes the XML data transmitted through ALC/LCTsession and if the analyzed data is filed-based service then it isoutputted to the FDT Handler 154 and if it is a data for service guide,then it is outputted to the SG Handler 190.

The FDT Handler 154 analyzes and processes the File Description Table ofthe FLUTE protocol through the ALC/LCT session. The FDT Handler 154 iscontrolled by the NRT Service Manager 210 if the received file is forthe NRT service.

The SG Handler 190 gathers and analyzes the data for the service guidetransmitted in XML structure, and then outputs to the EPG Manager 200.

The File Decoder 157 decodes the file outputted from the FileReconstruction Buffer 152, file outputted from the Decompressor 155, orfiled uploaded from the third storage unit 156 using the pre-selectedalgorithm and outputs to the Middleware (M/W) Engine 230 or to the A/VDecoder 141.

The M/W Engine 230 interprets and executes the application, which is thedata of the file structure. Further, through the Presentation Manager240, the application may be outputted to an output device such as ascreen or a speaker. In an embodiment, the M/W Engine 230 is a JAVAplatform based M/W Engine.

The EPG Manager 200, depending upon the input from the user, outputs theservice guide data after converting into a display format received fromthe SG Handler 190 to the Presentation Manager 240. The ApplicationManager 220 manages the handling of the application data received in afile format.

The Service Manager 160 gathers and analyzes the NRT service signalingdata transmitted through the NRT service signaling channel or thePSI/PSIP table data and creates a service map and the stores in thesecond storage unit 125. The Service Manager 160 controls the accessinformation of the NRT service that the user wants and controls theTuner 111, Demodulator 112, and the IP Datagram Handler 136.

The Operation Controller 100 according to the command from the userthrough the UI Manager 250, controls at least one of the Service Manager160, the PVR Manager 170, the EPG Manager 200, the NRT Service Manager210, the Application Manager 220, and the Presentation Manager 240, andexecutes the user's command.

The NRT Service Manager 210 manages the NRT Service transmitted incontent/file format through the FLUTE session on the IP layer.

The UI Manager 250 delivers the user's input through the UI to theOperation Controller 100.

The Presentation Manager 240 provides the user through a speaker and/ora screen at least one of the audio and video data outputted from the A/VDecoder 141, file data outputted from the M/W Engine 230, or serviceguide data outputted from the EPG Manager 210.

As described above, according to the embodiment of the presentinvention, since an RT-specific service guide screen may be easilyshifted to an NRT-specific service guide screen, or since anNRT-specific service guide screen may be easily shifted to anRT-specific service guide screen, the user may be able to convenientlyuse the NRT service and the RT service. Also, by providing a storagemedium management screen that can modify the storage space, the presentinvention allows the user to easily allocate and modify the storagespace for the operator contents. Furthermore, by providing a function ofsorting contents by at least one of content name, channel name, date ofrecording, and content size in the list of recordings screen, whichincludes the contents stored in the storage medium, the user can easilyrecognize the contents stored in the storage medium.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A method of transmitting a broadcast signal fornon-real time service, the method comprising: generating the broadcastsignal having the non-real time service, signaling data for signalingthe non-real time service and file delivery table providing a means todescribe attributes for files associated with a non-real time content inthe non-real time service, wherein the signaling data includes a servicemap table containing service-level attributes for the non-real timeservice and a non-real time information table containing informationdescribing non-real time contents available for download to storage in abroadcast receiving device, wherein the service map table includesinformation used as a linkage to a non-real time information table,wherein the non-real time information table includes content linkageinformation used to link metadata in the non-real time information tableto at least one file described in the file delivery table associatedwith the non-real time content; and transmitting the non-real timeservice via a broadcast channel, and the signaling data via a servicesignaling channel, wherein the non-real time information table furtherincludes playback delay inclusion information indicating whetherplayback delay information is present in the loop for signaling thenon-real time content, and playback delay information specifying numberof seconds following reception of a first byte of the non-real timecontent the broadcast receiving device shall wait before playback maystart, while buffering a incoming stream, and wherein the non-real timeinformation table further includes content number information indicatinga number of the non-real time contents described by the non-real timeinformation table.
 2. The method of claim 1, wherein the non-real timeinformation table further includes update information specifying thenon-real time content is to be updated periodically.
 3. The method ofclaim 1, wherein the non-real time information table further includestext fragment information specifying whether a text fragment is presentin the signaling data for the non-real time content.
 4. The method ofclaim 3, wherein the text fragment provides texts describing thenon-real time content.
 5. An apparatus for receiving a broadcast signalfor non-real time service, the apparatus comprising: a tuner configuredto receive the broadcast signal having the non-real time service andsignaling data for signaling the non-real time service; wherein thesignaling data includes a service map table containing service-levelattributes for the non-real time service and a non-real time informationtable containing information describing non-real time contents availablefor download to storage in a broadcast receiving device, wherein theservice map table includes information used as a linkage to a non-realtime information table, wherein the non-real time information tableincludes content linkage information used to link metadata in thenon-real time information table to at least one file described in a filedelivery table associated with a non-real time content, wherein the filedelivery table providing a means to describe attributes for filesassociated with the non-real time content in the non-real time service;and a storage configured to store the at least one file associated withthe non-real time content; wherein the non-real time service is receivedvia a broadcast channel, the signaling data is received via a servicesignaling channel, wherein the non-real time information table furtherincludes playback delay inclusion information indicating whetherplayback delay information is present in the loop for signaling thenon-real time content, and playback delay information specifying numberof seconds following reception of a first byte of the non-real timecontent the broadcast receiving device shall wait before playback maystart, while buffering a incoming stream, and wherein the non-real timeinformation table further includes content number information indicatinga number of the non-real time contents described by the non-real timeinformation table
 6. The apparatus of claim 5, wherein the non-real timeinformation table further includes update information specifying thenon-real time content is to be updated periodically.
 7. The apparatus ofclaim 5, wherein the non-real time information table further includestext fragment information specifying whether a text fragment is presentin the signaling data for the non-real time content.
 8. The apparatus ofclaim 7, wherein the text fragment provides texts describing thenon-real time content.